PHILADELPHIA F0uN DRYMEN'S AssOCIATION, INC.

Transcription

1 C. F. HoPKINS, PRESIDENT B. H. JOHNSON, VICE-PRESIDENT AJAX METAL COMPANY P. D. W000 & COMPANY DIRECTORS PHILADELPHIA F0uN DRYMEN'S AssOCIATION, INC. INC. ESTABLISHED 1891 H H. COOKE INCORPORATED 1902 OLNEY FOUNDRY CO. UNDER THC LAWS OF PENNSYLVANIA G. L. COPPAGE PUSEY & JONES CORP. EARL S. SPARKS SECRETARY-TREASURER DIRECTORS J. A. DAVIES W ESTINGHOUSE ELEC. & MFG. CO L. U. PARK PARK & WILLIAMS, INC. C WALTER YOST THE MIOVALE COMPANY MEETINGS SECOND WEDNESDAY OF EACH MONTH EXCEPT JULY. AUGUST AND SEPTEMBER AT MANUFACTURERS' CLUB Tanuar~ OFFICE OF SECRETARY-TREASURER PHILADELPHIA, PA. To the Members, Gentlemen: Accompanying this communication is the stenographic transcript of the discussion on The Operation of the Cupola. Much valuable information on this subject was contributed by practical foundr3rmen and we recommend that it be read by your foundry executives and the man in charge of your cupola. The cost of this manuscript was considerable and the Board of Directors decided to circularize it to the members as an evidence of the worthwhile service of the Association Additional copies may be secured for 1.00 on application to the Secretary. Very truly yours, PHILADELPHIA FOUNDP.YN' S ASSOCIATION, INC. ss/c End. Secretary-Treasurer

2 C. F. HOPKINS, PRESIDENT B. H. JOHNSON, VICE-PRESIDENT EARL S. SPARKS AJAX METAL COMPANY R. D. WOOD & COMPANY SECRETARY-TREASURER DIRECTORS GEORGE M. BENKERT FAIRMOUNT FOUNDRY, INC. H. H. COOKE OLNEY FOUNDRY CO. B. L. COPPAGE PUSEY & JONES CORP. PHILADELPH A FOUNDRYMEN'S ASSOCIATION, INC. ESTABLISHED 1801 INCORPORATED 1902 UNDER ThE LAWS OF PENNSYLVANIA DIRECTORS J. A. DAVIES WESTINGHOUSE ELEC. a MFG. I L. U. PARK PARK & WILLIAMS. INC. C. WALTER YOST ThE MIDVALE COMPANY MEETINGS SECOND WEDNESDAY OF EACH MONTH EXCEPT JULY, AUGUST AND SEPTEMBER AT MANUFACTURERS' CLUB OFFICE OF SECRETARY-TREASURER 1623 SANSOM STREET, PHILADELPHIA, PA. January 12th, Mr. Foundryman: The enclosed transcript of discussion on The Operation of the Cupola contains much valuable information contributed, by practical found.rymen and should be read by your foundry executives and those directly in ch,rge of cupola operation. The distribution of this sort of information is the kind of thing that makes membership in this Association worthwhile. Last year we distributed a transcript of an excellent address by that eminent foundry authority, Dr. Moldeflk. Membership in this Association affords opportunity for contact with those in your own industry and with those supplying materials used in production together with a regular monthly discussion of a timely and pertinent foundry topic. One suggestion prompted from these discussions, one load to the solution of a foundry problem, would more than compensate for the nominal cost of membership - entrance fee lo.00; annual duos This Association has served the foundry for forty years and your support will not only enable it to continue but to enlarge its services. May e have your application for membership? Very truly yours, PHILADELPHIA FuIJNDRIMEN'S ASSOCIATION, INC., ESS/C End. Secretary-Treasurer

3 DISCUSSION OF STANDARD PRACTICE FOR 54" CUPOLA OPERATION of P B 0 C E E D I N G S of the PHILADELPHIA FOU1JDRYMEN'S ASSOCIATION MONTHLY MEETING held NOVEMBER 12TH, 1930 ** Adelohia Reporting Bureau, Hotel Adeiphia, Philadelphia, Pennsylvania.

4 PRESIDENT HOPKINS: As announced in our bulletin, we are running a meeting all by our lonesome tonight, and from what I know of some of the gentlemen that are going to speak, I think we will have just as good talent as we have when we go outside. The discussion, is on the Standard 54" Cupola, and as we expect to make a report of this discussion we have a stenographer to take down our remarks. The meeting will be led by our good friend, Mr. Greenstreet. I am sure, that he will tell us a lot of good things, and stimulate discussion by other men. Mr. Greenstreet will take charge of the meeting. CHAIRMAN GREENSTREET: Mr. Sparks will read the recommended practice drawn up for 54" cupolas. This recommended practice was gotten together by a committee of the American Foundry-men's Association, who asked us to discuss it, and make any comments we saw fit, and report back to them. I will have Mr. Sparks read the recommendations, and then we will go into the meeting. MR. SPARKS: (Reads "Recommended Practice Drawn up for 54-inch Cupola operation".) CHAIRMAN GREENSTREET: I think we had better start with the first paragraph, which is the lining of the cupola. "Lining: (A) For lining up a new cupola or relining an old one, a good grade of cupola block of proper dimensions should be used. The block should be laid up with close joints and filled between with a fireclay mixture. Various mixtures are used." I think we will all agree that we ought to line up with a good grade of cupola block, we ought to have close joints. The fireclay mixture depends a lot on the length of heat. "(B) The shape of lining depends on practice and may be classified under two types, as follows: 11 (1) Straight side; that is, straight from bottom doors to charging door. 11 (2) Boshed; that is, a 3 to 6 inch projection at top of tuyeres and tapering off to the straight side just above melting zone." No doubt some of the gentlemen present have used the boshed lining, and others have used the straight lining. Mr. Schaal, you have had a lot of experience with cupolas; what is your practice? MR. ROBERT B. SCEPAL (Roberts & Mander Stove Co.): Our usual practice is to use a bosh. CHAIRMAN GREENSTREET: How far do you bosh it above the tuyeres? MR. SCHAAL: Mr. Hamburg tells rue it would be about three feet above the tuyeres. We are not sure of that, however. We don't know exactly how high that would be. In drawing up a general set of specifications like these, it is largely a matter of preference whether you are going to use a straight side - 1 -

5 cupola or whether you are going to have a bosh. As a matter of fact, it is largely a matter of indifference on a cupola of the smaller sizes, but on cupolas of larger sizes, a bosh is quite preferable to a straight side cupola, because it aids a lot in penetration of the blast. On this 54-inch cupola I would say that it made no difference, or at least very little difference. CHAIRMAN GPEENSTREET: What size is your cupola? MR. SCHAAL: 66-inch. The only time when a bosh would be of advantage in a 54-inch cupola would be in case the air could not be delivered at sufficient pressure to insure proper penetration. CHAIRMAN GREENSTREET: You wouldn't say there was any danger of the tuyeres becoming bunged by the molten iron slipping down the side in front of the tuyeres? Do you think it might be of advantage even on small cupolas to have a bosh for that reason, or not? MR. SCHAAL: I don't think that there would be very much danger of that, although a slight shelf above the tuyeres is certainly a protection; there is no doubt about that. CHAIRM.AN GREENSTBEET: Mr. Maloney, what are your ideas on that? MR. MALONEY (Cramp-Morris Foundries): We line straight like you have shown it on the picture. CHAIRMAN GREENSTB2T: And you have the 54-inch? MR. MALONEY: Well, almost the same inch. 72-inch, lined down to a 57-inch. We line straight. CHAIRMAN GREESTREET: You run comparatively long heats, do you not? MR. MALONEY: I would say on an average of 20 tons. CHAIRMAN GREENSTREET: And you have never had any trouble with tuyeres bunging on account of the straight lining? MR. MALONEY: No, and we have taken 50 tons out of the same cupola. CHAIN GREENSTREET: Of course, this recommended practice says, "The shape of the lining is dependent upon p-ractice and may be classified under two types". Has anybody anything else to say about that? MR EDWARD BNKERT: (Fairmount Foundry Co.): On the mixture of fireclay, I think consistency should be mentioned and whether the brick should be dipped. CHAIRM.AN GREENSTREET: Personally I believe in dipping a brick in what we call the "soup" and driving them up as tight as you possibly can got them; that is, having no more play in the joint than you can possibly have. MR. BNKERT: I think those recommendations should state in there rust the consistency

6 CHAIRMAN GREENSTREET: I thought that, too, but thought somebody might raise the question. I am glad you did. I like to dip a brick in a tub of mortar that is about the consistency of soup, and drive it up as hard as you can, and when you put the last brick in have it a little bit tight, and lay a piece of timber on top and come down with a sledge and bring it up so the clay squirts out of all the joints, giving you a very tight joint, almost a solid lining. We have always got to have a cushion of grouting between-the brick and the shell to take care of expansion, but that has always been our practice. However, I have seen others simply smear something on the edge of the brick and drive it up tight then. But I like to use straight fireclay mixture lining up the cupola and put it in like you had a grudge against the concern you were working for, and thought it was good economy, because it makes a good, real tight joint, and you don't have a lot of clay to fall out and cause trouble. MR. DOIJGHTEN (Pusey & Jones): The question of a shelf right above the tuyeres for the protection of the tuyeres, should be brought out. CHAIRMAN GREENSTREET: That was the question I asked Mr. Schaal, whether he found any advantage in that or whether he thought that even on small cupolas we shouldn't follov that practice. MR.DOtTGHTEN: Well, even the straight lined. CHAIRMAN GREENSTREET: Mr. Schaal uses, on his 66-inch cupola, a bosh, because he wants a better blast penetration. Naturally, bringing the air in from the side, he wants to reach the center with the blast. MR. DOUGHTEN: I didn't mean exactly a bosh, but with the straight lined cupola right on top of the tuyeres, the tuyeres should be protected with a little shelf. CHAIIMAN GREENSTPT: Even though you had a straight lining you think we should bring it a little beyond the tuyeres? MR. DOIJC+HTEN: Yes. CHAIRMAN GREENSTREET: I think that is good practice; that is a good point. Mr. Maloney, do you do that? MR. MALONEY: (Cramp-Morris Foundries): Our top plate that we put on top of the tuyeres extends about an inch out beyond that. CHAIMT GREENSTREET: Does anybody care to say anything more about that? -- (No comments) "(c) After each heat, chip out badly burned brick and patch with new brick, maintaining the original outlines as closely as possible." I 'think that is what most people do. A new breast brick or tap hole should be used if previous one has become too large for the desired flow of molten metal from the cupola." It looks to me as if those things were put in really for novices; everybody knows you have to maintain your hole, or should, the same size. rz - (_1 -

7 "The tap hole should be about 1 inch in diameter at the shell for intermittent tapping and should not be over 2 or 3 inches in length." There is a question there, that some people might object to. Of course, they are always talking here about a 54-inch cupola; they haven't mentioned any other size. And I can't see any objection to an inch hole in a 54-inch cupola if we are going to tap it intermittently, because you can close it whenever you are ready to, and open it when you are ready. If you get it a little too small, your iron runs on the dead side and is apt to cause a little trouble plugging it up. Does anybody want to say anything about the size of tap hole? plenty, MR. EDWARD BE1KERT (Fairmount Foundry Co.): I think that length is 't you? CHAIRMAN GREENSTREET: I like to have it as short as I can get it, MR. BENFRT: I think two inches is plenty. I think one to two inches would be better than two to three. CHAIRMAN GREENSTREET Yes, I think two inches is enough. MR. COPPAGE (Pusey &.Tones): In patching up, (I see a lot of brass men here) in our family we run a three ring circus, melting brass and heat resisting and cast iron. We had a man that patched with broken crucibles, and seemed to get very good results. And when he was relieved of his job and it was given to another man, he didn't seem to have the same success in patching up, and this fellow said, "Well, I can do as good a job as the other fellow if they will just let me have the crucibles." I thought we might ask some of these brass fellows if there vas really any virtue in it. CHAIRMAN GREENSTREET: I would think anything that would stand a lot of heat would be a good thing to patch with. MR. COPPAGE: I was wondering if anybody else had used broken crucibles to patch with. QUESTION: Do you use ground crucibles for that? MR. COPPAGE: Yes. MR. SCHLEY (Pennsylvania Bronze & Brass Co.): I would say in connection with the crucibles, that a good many years ago, before they used the silicon carbide, they would be of little or no use to a cupola, but since the time that they have been using silicon carbide, it would be of quite an advantage. I believe Mr. Spare could enlighten us a whole lot on that. MR. SPARE (.Tanney Cylinder Co.): On the question of using broken or ground crucibles for patching cupolas, crucibles are made of about 66% graphite, - were made, years ago, about 66% graphite, more or less Ceylon, and 33% Klingberger clay, Germany. Now I doubt whether graphite would be so advantageous; I am rather inclined to believe with Mr. Schley that the introduction of carborundum (he calls it silicon carbide, which is right) -- silicon carbide into that clay, would make it very refractory, and it wouldn't cut away. It would be a very good refractory for patching. Crucible clay, plus silicon carbide, - it would be a binder for the - 4 -

8 silicon carbide. I think that would be a very, very good material for patching cupolas, Mr. Coppage. You can get that from any good brass foundryman if he uses silicon carbide pots today, and I think he would be glad to get rid of his crucibles. I don't think it would cost very much. A lot of them are available on the market. So I believe the present pots that are made with silicon carbide would be very satisfactory for patching. MR. W. F. CLE1VfEtTS (Fuller-Lehigh Co.): I have had occasion to patch up a cupola with silicon carbide, mixed up with high grade fire clay. I couldn't get anywhere with it at all. It came right out just. the same as a 9-inch brick. We had a cupola burning away badly over the tuyeres and it so happens in our work we have silicon carbide. I took a rich fire clay, 3,000 fusing temperature, made a good paste of it and put it on. It came out just the same as the fire brick would. MR. HOPKINS (Ajax Metal Co.): Mr. Greenstreet, for the benefit of the iron men who contei:plate the use of crucibles from a brass foundry, I would like to caution them to be sure that there is no brass left on the crucibles. It will oxidize, lower the fusing point of your patchings and run out as fast as you put it in and contaminate your iron, if there is much of it there. HAILAN GFEEhSTREET: I was going to ask somebody in the brass business is they thought the brass or the other metal, non-ferrous metal, melted in a crucible, would have any bad effect. I think the point Mr. Corage brought out about his former man having good luck with the crucibles, after hearing all the other people speak on the subject probably there was a lot more to that than just the crucibles. It might have been the care that the man used in chipring out the cupola and how well he renved the sla. I have seen men who put in a lot of work on a cupola, and all the stuff they put in fell cut again, simply because they didn't use enough care in removing slag. The slag gets hot, wheii the blast goes on and the cupola gets heated up, and that slag starts to molt. If you haven't been very careful before you put your patching in, by it makes a sort of parting and causes it to slip and everything falls away. Sometimes the cupola man can keep your cupola in good repair even though he doesn't have such wcndorful materials, if he is careful in what he does. I just wondered if there might have been something to that, aside from the fact that you used crucibles. MR. COPPACE I wouldn't be surprised. As I understand it, your cupola tender tends to cut down your tuyere area to get your penetration of blast, and therefore he cuts down the scarification or whatever you 7ish to call it, and if he can keep that scarification down, then he has less patching, and in that event you get, as I understand it, poor cupola practice, and we think that you want to get plenty of scarification and plenty of renewal in your melting zone, in order to get good cupola practice. I may be wrong on that, but that is our idea. CHIRM.AN GPEENSTRET: Sometimes you find a man that does too much patching. (I just thought going along that I would make a few remarks too; I guess some people expect me to say something rather than ask a lot of questions.) But a fellow may put in too much patching and cause you trouble. Another fellow may not put in enough, and instead of having a 54-inch cupola, you may have a 60-inch cupola, and all your calculations have been made on a 54inch cupola. When you undertake to reduce your coke with the idea of economy, either all the - 5 -

9 way through, or sometime during your heat, and reducing your blast proportionately to get the proper combustion, you may find you are not getting blast penetration, and that your cupola not only runs cold, but also slow. I had that happen one time, and even though I was using a minimum amount of coke, I in.- creased the blast a little bit and the iron became hot immediately. Now I will admit that is an exceptional case, you would sort of have to assume that your cupola man had done something that you didn't intend him to do. So you would know that you have reduced your coke to the point that this ought to be enough blast and that your iron ought to come through all right. And when she starts to slow off and come a little bit dull, you might say, "You damned fool, you ought to put more coke in". But, knowing the condition of the man's mind and how he has been working, and knowing him very well (he should be studied) then you lift your blast a little bit and you get that penetration you don't otherwise get, and it may tide you over a bad point I thought I would mention that, because I have seen things this year go awry when according to all the things that I knew that had happened it should come right. And sometimes you want to do just the opposite to what you would do had you done the whole job with your own hands. Of course, having done the same job with my own hands, and run off heats of thirteen hours and above, I could pretty near figure about what the fellow might do or might not do, if he got a late start or something else happened to him. MR. COPPAG-E (Pusey & Jones): As I understand it, it is understood the blower is hooked up with a variable speed motor. Was there any mention of that in there? CHAIRN GRENSTREET: Really, there wasn't. MR. COPPAGE: Then if you are going to do what you suggested, it seems to me that that is an essential thing. CHAIRMAN GREENSTREET: One ought to use a variable speed motor, either that or a cone pulley. He should be able to change his speeds; that is, If you are going to run a cupola for an hour or two hours or three hours, you can get away with 'most anything. And I'll say the great majority of the foundries in this locality don't run more than two or three hours, but there is the occasional time, and you have run into it, when you probably want to run six or eight hours. Then, if your iron commences to go a little bit bad along about eleven o'clock, you have got to know what to do in an emergency, and those are the things we will come to a little bit later on. "For continuous operation the size should be adjusted to the melting rate. Its location is just at the level of the sand bottom." I don't think anybody will find much fault with having the tap hole ad.- justed to the melting rate where you are going to run continuously; that just seems to be common sense, unless you want to run a lot of slag out of the hole. "(E) The slag hole should be located from 2 to 4 inches below bottom of tuyeres. Its size depends on thickness of lining and on size of cupola, usually from 1 to 2 inches either round or square." It speaks here about the size depending on the thickness of the lining and on the size of the cupola. The cupola, of course, which we are discussing Is a 54-inch cupola, so the size seems to be fixed.

10 Mr. Newland, do you know any reason why the location of that slag hole should be anywhere from 2" to 4" above the tuyeres? MR. NEWLAND (American Engineering Co.): There are times, Mr. Greenstreet, when I have almost had to have it up close to the tuyeres to gather as many pounds as I could in the bath. We are taking a chance sometimes on a very fast melt, throwing a little slag over in the tuyeres. If you are slagging properly I don't think you need to fear that. Ordinarily, I think it is a pretty good distance to keep, - the distance you mentioned. At times some foundrymen here have that con dition, where they are trying to get every pound melt in the bath, especially with high test metal. So even if it is only an inch below the top of the slag hole, sometimes we get away with it. CHAIRMAN GREENSTREET: Did I understand, Mr. Newland, you want to collect as much on your hearth as you can, to get a thorough mixture and maybe another time in order to pour a casting of a certain weight to be sure your mixture is right? MR. NEWLAND: Yes. CHAIRMAN GREENSTREET: Has anybody any fault to find with that? MR. HARRY TITGEN (Titgen-Eastwood Co.): We generally put the slag hole 2-i" below the bottom of the lower ti.were. Then you are carrying iron on the bed sometimes that is too low, and the foundrymen want it higher. But in the other case, on continuous pouring, they drop them down within - a fellow has his bed tapered, say It is 6 Inches at the bed, and at no time will he carry over 2 inches of iron on the bed. Then we make It so that It is 10 or 12 inches below the bottom, tuyeres so he keeps it slagging from the back. Of course, people running continuous heats often get slag from the front. But those successful with slagging are still slagging from the back, which Is the proper place to slag a cupola. CHAIRMAN GrtETgNSTREET: Do you think a cupola would run longer, or don't you, with the slag hole far removed from the tuyeres? -- that is, lower down. MR. TTTGEN: Well, it will run longer and keep more slag from being carried out through the tap hole, keep the iron cleaner; that is, in continuous pouring. CH.&IBMAN GREENSTREET: The reason I mentioned that, the Bessemer cupola carries the slag hole about eighteen inches below the tuyeres and has a hearth of about five feet, and they run as long as the lining will last. They travel on the assumption and have pretty nearly proved the point that the further you keep the slag away from the tuyeres, the less danger there Is of freezing up around there. They think there Is a danger if you get it too high that even though It might be two or four inches away, that she might become plugged up and cause your slag to rise in the tuyeres. And most people who are running long heats -- when I say that I mean all day --- like to have it as low as they can get it, so I guess that Is the fellow that would want to go about four inches. The only reason I am discussing this Is to give an insight into It to the fellow who probably Is running a short heat. It isn't necessary for him to have it so low perhaps, and the fellow running a long heat, in order to be absolutely safe, so that the man on the cupola doesn't have to watch It every minute, he would probably drop down to four inches. I imagine that is what they had in -9-

11 mind when they wrote this recommendation. your conditions. You Work 2 to 4 inches, according to MR. BEMERT (Fairmount Foundry Co.): This recommendation doesn't say what tonnage is going to be run out of this cupola, Is that continuous? CHAIRMAN GREENSTREET: It says you can run continuously or intermittently, and that you can have your slag hole either two or four inches below the tuyere anywhere in there, which to my mind would cover a pretty good range for length of heat. They probably had on this committee men that were running different length heats, and one fellow said, "Well, I run mine two inches", and another fellow said, "Well, your heat is pretty short. The reason we run ours four inches is because we are afraid the slag hole may become bunged, and the cupola man not being on his job, we may get an overflow, so I prefer to run mine 4 inches on a heat of that length." Now I don't know that that happened, but It Is certain that pretty nearly all these recommendations are more or less of a compromise, so I think perhaps that is why the 2 to 4 inches is stated, because 2 to 4 inches is a big spread. What do you think, Mr. Schaal? MR. SCHAAL (Roberts & Mander Stove Co.): My idea on that specification is that they have simply put those limiting figures on the distance between the tuyeres and the slag hole so that you won't get it too close to the tuyeres. It doesn't imply how far below that you are going to go with it. I simply think that Is an upper limit in that specification. CHAIRMAN GPEENSTREET Yes, you can go as low as you please. Now this should bring a 1t of argument, with the stove man, the car wheel man, the pipe man, general machinery and jobbing man, and the cupola manufacturer -- this thing that everybody has argued about for ages. "II. Tuyeres: The area of the tuyeres should be approximately onethird of the area of the cupola taken at the tuyeres." Now remember, that does not say "at the melting zone", but "taken at the tuyeres". "The height of tuyeres should be from 10 to 20 inches above the center of sand bottom, depending on amount of iron required at one tap. The tuyeres should be as nearly continuous as possible, with a vertical opening 3 to 5 inches in height. For ordinary conditions, use only one row of tuyeres." And it doesn't tell how many, but states, "Make them as nearly continuous as possible". MR. HARRY TITGEN (Titgen.-Eastwood Co.): When I am going in to sell a cupola to a man, I feel him out as to just what he has been doing in life, and try to avoid an argument with him. But from practice that I have had in the foundry field, twenty years now, the first thing I should think that they would put In this pamphlet, is that measurement be taken at the inside shell of the tuyere, not at the tuyere opening of the lining. That is where your area is dete'mined, because you can flare a tuyere casting, make it almost continuous around, but it is the opening in the shell that determines the area. MUM

12 r1airlan GREENSTREET: In other words, you think you can't get any more water out of a hose than will go through the nozzle. MR. TITGEN: Yes. Now as far as the size goes, instead of making them 3 inches I would rather have them 5, to get the volume of air in there. Because you have got to have the oxygen in there. OHAIPILAN GREENSTREET: Would you think, then, if you had them 5 inches high, with a continuous opening all the way around, 54-inch cupola, which would be approximately 165 inches in circumference, that you would have the air meet in-the center of the cupola, or would you carry a cold spot in the center? MR. TITGEN: If you have your area of your opening, as it has here, you would have your opening. chaian GRESTHEET: But then you wouldn't have a continuous tuyere. MR. T1TGEN: No. CHAIRMAN GRESTBEET: It says "at the lining", and wants it as nearly continuous as possible. MR. TITGEN: And we build our cupolas so that they are. The edge of the tuyeres, at the lining, are almost continuous around there. The tuyeres meet, the inner edge of the tuyeres. But we don't go to that same ratio for all cases. CHAIRMAN GREENSTREET: Would you on a 54-inch cupola? M.R. TITGEN: It would depend on the grade of work the man wanted. CHAIRMAN G? STREET: Do you think that really has so much to do with it, as whether or not the air is going to meet in the center of the cupola or whether it is going to cross and make a back lash? You see you are really putting air in, then. The endeavor is to melt iron without deteriorating it, and if possible to improve it Dr. Moldenke isn't here, and perhaps I shouldn't say thi$ when he is not here; but he has made the assertion on many occasions that a cup1.was simply a melter. I have alvays contended that up to a certain point it was a reduction furnace, that you could get out better metal than you put in, if it was properly operated. Now your air, of course, should be oxygen -- not 100%, but you put the air in with the idea of getting oxygen. You also add coke with the idea of getting carbon to form as near as possible a complete combustion, assuming that the cupola is only 35% to probably 40 efficient anyhow. But if you destroy your carbon through too dense a penetration of the air, you get a waste; in other words, you cross whip the penetration of air as it comes and get a back lash. Now don't you think that really a cupola ought to be designed with the idea of having your air just barely touch in the center? MR. TITG: You do that when you bring your air in your tuyeres to a percent of your melting zone area.

13 CHAIRMAN GPEENSTRET: That is true, provided it is right. Now what I want to find out is, do you agree that 3 to 1 is the right ratio in a 54-inch cupola, or don't you? MR. TITGEN: No. CHAIRMAN GREENSTREET: Neither do I. Does anybody else agree on that, or don't they? Do you think the ratio should be 3 to 1 on a 54-inch cupola, 'or should it be4tolor5tol? MR COPPAGE: I don't know what it should be; but in my opinion you should get the t.uyeres large enough, for this reason. If you look at that drawing, it looks as though the coke is in the tuyeres. It is shown to represent the fact that your coke is in front of the tuyeres. Therefore the coke chokes the tuyeres, and the air must go through that coke. The amount of slag that you have got on your coke, plus the coke, tends to control your penetration. So that we have no measuring stick to tell us what penetration we are going to get. But I would tend to agree with Harry that I would have them too large rather than too small. Does that answer your question? CHAIRMAN GREENSTREET: Yes, except that I think he kind of disagreed with you there. He doesn't believe that you ought to drop down to 3 to 1. He don't believe you would get a hot center. Is that right, if you had too much tuyere area? MR. TITGEN: If you had too much tuyere. Oh, there is a case of getting too much tuyere, sure enough. CHAIRMAN GREENSTREET: Well, what would you say that ratio should be? MR. TITGEN: 4 to 1, on a 54-inch cupola. CIÜIR'IAN GREENSTREET: That is what I want to get, -- something definite. MR. Tr2GSN: I had an experience about a year ago, - a plant wanted 2800 degree iron right along, They wanted light stuff. I was never sold before on a far. blower, or this new type blower coming out, because I wanted a positive pressure blower, and know the volume of air that was going in. And they asked me to come up, and after we built the cudola, see it in operation, and sell me the idea of this new blower. Well, I had gone up, and spent a couple of days there, and the first heat went off in great shape, and they said, "Well, now, you advocate lov pressure and the volume of oxygen there for combustion".. I said "Yes". "Well", they said, "we are going to shov you something today." Well, we built that cupola (it was a 54-inch cupola) 4 to 1. And they started on the blast. I saw 2800 and 2825 degree iron brought down at 4-i- ounces. The tuyeres were large, the volume of oxygen got in there with the sort blast. It had the affinity for carbon for combustion, and it was perfect combustion. Not only that; mostly all the cupolas you look into through the sight holes the iron comes down like rain, raindrops. It wasn't so there. There were just rivulets running down; there were no drops at all. Less oxidation, and getting out as much from mother earth as you possibly could without destroying any of the properties. sure. I was sold on the blower because it put the volume there at low pres

14 I had another case not long ago in Hartford. A man wanted to run a small cupola on continuousoring, and he got into a lot of trouble. I put in equipment there, and we started the heat off. After we had run about four hours, (they had a four foot hearth in front of the cupola where they had done some mixing of the metal) it started to blow. This was the third day I was there. The fellow said, "Well, Titgen, we're in the same fix as the other fellow was; we're bridging." He said, "She's starting to blow". I said, "How about your breast brick?" He said, "I can't get to it; everything is red hot". It was that same type blower. We shut it down to see what was wrong, and we saw that the breast was cracked and that is where she was coming through. I guess it was down twenty minutes, and ve started the blower arain to bring the rest of the heat down, and inside of four minutes there was 2600 degree iron there. Now those tuyers were on the same ratio as the others. HAIAN GRESTREET: What was the ratio? MR. TITGEN: On that cupola it was about 4-3/8. CHAIIAN GREEI'STPEET: What size cupola? MR. TlTG: That was lined a 63. CHAIRMAN GREENSTREET: What was the other? - 54? MR. TITCEN: The first one I spoke of? - Yes. CHThN GREENSTBEET: What was the ratio there? MR. TITG 4 to 1. The 4-inch was 4 to 1. I would like to get the vole of air in there at as soft a pressure as possible. HAIRM.AN GREENSTREET: Did you have double tuyeres or single tuyeres? MR. TITGEN: Single tuyeres. They had the upper tuyeres there, but they weren't to be used. 0HAIMAN GREENSTREET: Do you use upper tuyeres, Mr. Schaal? MR. SCHAAL: Yes, we do. Then vie want to bring down a big heat in a short time. There is another question not included in there except that it simrly states that they want one row of tuyeres. And when you are making out general specifications, I certainly would agree with it. I don't see any reason for really bringing up two rows of tuyeres in a general specification like that; it is something that must be used with --- well, you have to be judicious about it. There are some cases where two rows of tuyeres will serve very much better than one, and there are plenty of other cases where two rows of tuyeres would just simply ruin everything, depending entirely on what you are melting and what coke you are using. Those t;o factors also enter into the size of the tuyere opening a great deal. The force that is necessary to cause proper penotration, when you are using a dense coke, is vary much greater than when you are using a light, coarse, open coke. Those things have to be considered. The pressures that you use are entirely different v..hen you are running a close, dense coke, melting heavy matorial, than when you are running a light coke that burns fast, and melting light scrap. Those things are quite variable, and when you go to

15 lay down any definite specification for tuyere area in a cupola, I would go about that pretty gingerly, because I don't think it can be done reasonably; it depends too much on what you are melting. MB. COPPAGE: I would like to have Mr. Doughten (he is our metallurgist in charge of our cupola) tell you just what our experience has been in that. MR. DOUGffTEN (Pusey & Jones): Well, we have tried pretty nearly all sizes of tuyeres. There is one thing I found out, by changing my height of tuyeres, my melting zone changed. Men I opened, gave about an 8-inch height, my melting zone dropped down very close to the tuyeres. When I gave the nozzle effect by narrowing it to 5 inches, 5 inches, to be exact, she came about right.. I would like to have somebody's opinion on that change of the melting zone. CHAIRMAN GREENSTREET: Do you mean when you make your tuyere high, the height from the sand bottom? MR. DOUGHTEN: I mean the tuyere itself; the tuyere box. CHAIRMAN GPEENSTREET: There is one man who stood them on their ends and got very good results, and cut out the top tuyeres entirely. We use top tuyeres; have to use single tuyeres. Personally, I like a top tuyere; I guess perhaps it is because it is the way I was trained. Everybody is trained a certain way and can't get away from tradition. A draftsman told me one time it was the hardest thing in the world to design anything new. If you looked at a chair, and tried to make another one that didn't look like it at all, you would have a terrible job on your hands. But I started in on running long heats and found that we liked the top tuyere. For instance, if the iron would go a little bit off, we had our bed made for the top tuyere and we simply closed the top tuyere and that helped us a little while, until the rest of the coke came down which we were putting in at the top. But I can appreciate what you say, running a heat with coal, coal, for instance, you always find that your melting zone is a lot lower; it gets down much lower in your tuyeres. I put in a bed of 15 inches above the tuyeres of coal, using broken coal, and had perfectly hot iron all the way through, and even at that low bed height, it came very slow, very nice and hot. MR. DOUG-H'TEN: Isn't it true that opening your top tuyeres gives you two melting zones? CHAIBMA.N GREENSTREET: You do get a second melting zone. like that? MR. DOUGflTEN: Isn't there a slight danger of oxidation in a case CBAIRMJLN GBEENSTBEET: I don't think so. I have heard that argued back and forth. I am not a chemist; perhaps you are, being a metallurgist. But the chemist tells you that when you put that oxygen in there, with the carbon, that you make what you call 002, and the gas rises above there and becomes 00, and by allowing a little oxygen to come in there, you again make CO2. In other words, you create that second melting zone and get the second combustion. Now there has been a lot of argument, about using upper tuyeres and lower tuyeres, of having to have an extra bed height. Thomas Stephen West made some experiments some years ago for the American Foundrymen's Association and found no bad

16 effects having 25% of his air (at least he said it was 25%, I doubt that) but what he did was to have 25% of his total tuyere area enter 12 inches above the lower row of tuyeres. Naturally, putting it in in small tuyeres, he cut down the intake of air, because of friction, I would say. However, he did blow some air right into the melting zone, he claims, without any bad effect at all. Some people say if you have upper tuyeres you have to increase the height of your bed, on account of the second melting zone. We have never found that true. I think it is more a lack of nerve than anything else. A man is afraid to leave his bed at the same height as he had it before, because he always knows he is starting up a second melting zone. Our bed today, for instance, is 36 inches above the upper tuyeres. We have had it 22 inches, have had it 16 inches with equally good results, considering of course the kind of coke we were using and everything else. But even using the 36 inches, with the coke we are using now above our upper tuyeres, we are still only using 2100 pounds of coke on a 56- inch cupola. Now, according to these recommendations, it says "From 2000 to 2400 pounds on a 54-inch cupola", using a lower tuyere. So if you save coke, and get a faster melt, really that is what you are looking for. But I do think it would require a little more watching, perhaps, and doing the same thing every day, be sure the cupola man follows the same practice day after day; otherwise he is liable to destroy your bed. But I think also, most beds are destroyed before the blast goes on. MR DOUGHTEN: Well, I feel that the higher you build your tuyeres, the closer to the lining you are melting, and I think there is a limit, that that ought to be watched very carefully at that height. CHAIRMAN GREENSTREET: I think you are right, because it is almost brought out with the upper tuyeres that you really don't increase your melting zone as much as you thought you would. That is why I say you don't really use any more coke on your bed, I don't believe, than you did with the lower tuyere. MR. DOTJGHThN: You are melting - right at the lining, really, instead of distributing it. There is a danger point there. CHAIRMAN GRETSTPT: Yes. Personally, I think that a cupola stands an awful lot of variation without getting in much trouble. I think most people get in trouble when they start fooling with a cupola. I have also noticed that a lot of people running foundries will not have such a good heat after the Cupola has been relined. I often wondered why that was, and looking into it thoroughly, I found out that the new lining hadn't been thoroughly dry. In other words, the cupola wasn't as dry as it was with the old lining. Sometimes I think we are tempted to place the blame for things where they really don't belong. MR. DOUGWFEN: I have noticed that if you leave a cupola go for a day or two before you patch it up, you are going to have that same trouble. It should be patched up the next morning to get your set. MR. EDWARD BENKERT (Fairmount Foundry Co.): What happens to the penetration after you run your cupola about two hours, when the front of your tuyeres are all black and it is pretty hard for the air to get through. Can you get the same penetration then as you would when you first put the blast on. CHAIRMAN GREENSTREET: I don't think, that you ought to get your tuyeres black whether you run four or six hours. I think the only reason you ought to get in trouble running a cupola is because your lining wears out. Most

17 people, have read McLaine's system, and the idea that the longer the cupola ran, the less fuel it took to operate, because a lot of heat was created. In creating this heat you destroy the coke that was in there. In other words, if you throw coke into a thing that is terribly hot, you consume it. And I think there is where most of us make a mistake, because we are going to run a long heat, we say, "Well, we won't need so much coke on this". So after you go three or four hours, your bed sinks. Your tuyere only becomes bunged up for two reasons, -- because you are using too much blast and not enough coke your bed is sunk, which is the same thing. You start up converting, and you commence to make steel. In other words, you are oxidizing your iron, decarbonizing it at the same time, starting right then to blow the carbon out of it. Your cupola should drop just as free, if you run ten or eleven hours, as though you had only run two hours. Most people have trouble with bridging on a long heat, simply because they don't use enough fuel to keep that bed at constant height. MR. BENTERT: We don't have a bit of trouble with bridging, but our tuyeres get black. And I am sure we don't get the penetration, we do in the early part of our heat. MR. DOUGHTEN: Don't you think the fluxing has something to do with that - keeping the insulation off your bed? CHAIPM.AN GREENSTREET: Yes, keep your slag out of your cupola; your slag should flow freely. Some people have it flow too freely, which causes the lining to cut. If you use too much limestone or too much fluorspar, you commence to cut your lining, which creates a lot more slag to get rid of. You should use enough limestone of good quality to keep her absolutely clean, but if you use too much limestone, you are apt to create a lot of slag that wasn't intended to be there. MR. HENKERT: Do you think you get the same penetration two hours after the blast is on as when you first put the blast on? CHAIRMAN GREENSTREET: I wouldn't say that, because your load will settle. That is the reason I believe in a variable speed motor, slip ring motor, so you can boost penetration. There is another reason for my saying if you are going to use all this great volume of tuyere area that you must be hooked up in order to get your penetration after your load is set. Most people, in our locality, don't run a Cupola that long to get into all that trouble, but out in Detroit, where they are making automobile cylinders they do. MR. BENKERT: I don't necessarily mean trouble; I said the tuyeres are black, which doesn't mean there is trouble. CHAIRvtAN GREENSTREET: No, but you understand it is just like a fellow who says, "Well, that casting isn't bad; you can sell it". But it is headed in the wrong direction. Your tuyeres should be nice and light and open and bright. MR. BENKERT: Red at all times. Well ours aren't. MR. DOUGHTEN (Pusey & Jones): I have heard the statement made if your lining doesn't burn out, you aren't getting good iron

18 CHAIRMAN GPEENSTBEET: I didn't mean burning; I meant cutting. I might have said burning, but I meant cutting. That same thing will hold true if you charge your coke unevenly so that your load slips. Some people want to charge a cupola level all the time. Somebody says you ought to charge your cupola all around the shell so it can't slip; you get that extra lift. My thought has always been to do it a little bit that way (Indicating lower in center than at circumference) so she would slip toward the center, never toward the outer edge. Another thing that is a good point brought out here, for charging your heavier stuff on the outside because if your light stuff melts it will always melt in the middle, which will automatically throw your load in; then you won't get bridging. I have seen people go up on the platform with long bars and break it when she hung, simply because something slid down on the side and grabbed in there. Then you get a cutting effect. On a cupola that is running all day, particularly where they are using heavy materials, look in the charging door, and you may find a little yellow flame. I used to call it a yellow devil. Well that means right there that the coke in that particular point is low, and that your charge has slipped and she is starting to cut your lining. It isn't a burning, it is really a cutting because there is nothing there, there is no coke under it and your iron is almost joining the other charge and then you get in trouble. MR. HARRY TITGEN (Titgen Eastwood Co.): Mr. Greenstreet, when you first line up a cupola, what do you think about putting in a fire and glazing the lining with rocksalt? CHAIRMAN GREENSTRT: I think anything like that is all right. MR. TITG: Do you think it should be recommended in this pamphlet? CHAIIMAN GRENSTBEET: I think it is a good plan to do it, but of course it only lasts for one heat. MR. BKERT: The first heat will glaze it just as much as the rocksalt will. M. TITGEN: Also, I think they should mention about the sand cushion between the shell and the brick. CHAIRMAN GREENSTREET: I think it is probably a good idea to have a cushion between the shell and the block - to take care of expansion. On account of shearing rivets or something of that kind? One row of tuyeres is sufficient, and on a 54-inch cupola, they ought to be 4 to 1 rather than 3 to 1? MR. TITGEN: If a foundrman was going to buy a cupola from me and wanted me to guarantee elven or twelve tons an hour, that is what his tuyere ratio should be, 4 to 1. CHAIRMAN GREENSTREET: You wouldn't say 5? MR. TITGEN: No, - 4. CHAIRMAN GREENSTREET: Everybody thinks 4 to 1 is all right?

19 MR. BKERT: Do you think the height of the charging door has anything to do with the tuyere areas? It naturally would build up more pressure, the more charges you put in. CHAIMkN GREENSTREET: Yes; but since you ask me what I think, I think that the scheme is wrong; I mean it is really making two wrongs to make it right. There is no end of how high you could have your charging door. You could have it so high that you couldn't get your air in the center at all. See? I think it is best practice, and these recommendations don't say a word about it here, to have a limit to the charging door above the bottom. MR. DOUGIUEN: On that question, we had a 56-inch cupola which was moved from the old foundry to the new foundry, and to make it fit, the bottom was lowered, and the charging door was raised, a matter of three feet altogether. In the old foundry, with the column of coke and iron up to the sill, we got hot iron. But with that three foot addition, you couldn't get such hot iron. But by keeping that column three feet, the original column, below the sill, we got the same iron as we got before. WAN GREENSTBT: I got $75 for telling a man that, once. He did the same thing, except he didn't do it that way. He put in a charging machine, and to get his charging machine in, he had to lift his charging door; and in doing that, he increased the depth of his charge from there down to the tuyeres, and he got into trouble immediately. So I told him, "Just charge at the height you used to charge", and his troubles were over. He could have increased his blast, as was said, to get it to the center. But to do that, he would have had to increase the amount of coke to take care of the extra oxygen he was putting in there; otherwise he would have lowered his bed. So the most economical thing to do was lower the depth. MR. TITGEN: Mr. Doughten, how high was the charging door originally? MR. DOUGHTEN: Twelve feet, approximately, from the bottom. MR. TITGEN: That is on a 66-inch? MR. DO[JGW.tEN: It was on a 56. Mr. Greenstreet, you were talking about method of charging. I ran half a heat with all my iron against the lining, all my coke in the center, and I had a terrible hang up. CHAIPMAN GREENSTREET: I don't recommend that, but some people do. MR. TITGEN: You put it up to me about the height of charging door for the operation of the cupola. We have got to stand back of them to give a certain tonnage in all diameters. We never recommend a charging door higher than three times the diameter of the cupola. CHAIBMAN GREENSTREET: That is what I would think. MR. TITGEN: 2* or 3 times, for the proper height. That gives the proper weight and allows the proper penetration of air. 16 -

20 CHAIRMAN GPEENSTREET: Well, it seems like everybody here thinks that 4 to 1 tuyere area is better than 3 to 1. "III. Bottom: (A) The bottom doors should be securely propped and rigid to eliminate possible cracking of sand bottom causing run out. (B) The bottom sand should be carefully rammed and slope from all directions toward the tap hole. The sand used should be a rich heap sand riddled and at same tamper as for molding. All new sand or sand too wet should not be used. It should be about 5 to 6 inches thick at the tap hole with a 1 or 2 inch pitch up toward the slag hole." Any objections to that? MR. TITGEN: On the bottom doors on the cupola, I would suggest that they put something to advise the foundryman to have these doors perforated, and on a 54-inch cupola they should be half inch holes, on 3 inch centers, to allow the gas to escape from the heating up of the sand bottom. CHAIR1VL91 GHEENSTRET: That is a good point, I think. Now we come to light up. "IV. (A) (B) Light Up: Flat wood is laid on top of bottom sand for protection while charging heavier wood. The wood usually is ignited through the tuyeres, or, better, by igniting oil soaked rags and dropping them on the wood bottom from the charging door, then adding sufficient 1,r400d to thoroughly ignite the coke. About two-thirds to three-fourths of the coke used on the bed is then added andlowed to burn through until the bed is cherry red all over. The remainder of coke is then added and leveled off ready for charging. The coke bed should be high enough to give melted iron in from 8 to 10 minutes after blast is put on. This usually will require from 2,000 to 2,400 lbs., depending particularly on height of tuyeres above sand bottom and the shape of the cupola well. The above amount should bring the bed from 40 to 50 inches above tuyeres. In starting a new cupola, it is safe to use a coke bed 45 inches above upper edge of tuyeres. The upper edge of the melting zone is easily determined by an examination of the lining after the first heat. It is a good plan to use a measuring rod for determining the height of the bed coke." M. DOUGHTEN: What does it mean, "eight to ten minutes"? Iron drops or over the spout? CRIRMMT GREENSTREET: I take it to mean the iron begins melting. It says, "to give melted iron" I imagine that would be the first iron you could see melted

21 MR. MALONEY: You can see it much sooner than that. I think it means over the spout. CHAIBMA.N GRENSTRYET: It takes us about seven minutes. Of course I believe really sometimes it drops a little before you can see it. Sometimes I believe you see it ahead of other days. But ours seems to show up, as nearly as we can tell, in about seven minutes, and we don't let ours run out; we hold it until it is full, and in about twenty-six to twenty-eight minutes, she's full, about 6,000 pounds of iron. Our cupola is 56 inches, when it is newly lined up. There isn't much difference between that and the 54 inch. I imagine the diameter wouldn't have a bit of effect on the time of melting, if everything else was proportioned properly. MR. MLLO1EY (Cramp-Morris Foundries): Wouldn't it be well if we could discuss the length of time that the iron is left to soak? In other words, after a cupola is filled up, the length of time that the iron is left to soak before you tap? In our case, we try to get an hour to an hour and a half, and in that way we can see melted iron dropping through the peephole in about three minutes. CHIBMAN GREENSTREET: How long a heat do you run? MR. MALONEY: About two hours. CHAIRMAN GREENSTREET: And your iron starts running over the spout in about how long? MR. MAlONEY: Eight minutes. Then we plug in. Most of the time we have it plugged in, but when we check up for the length of time that it runs over the spout, it will be eight to ten minutes. iron? CHAIRMAN GREENSTREET: How long before you see the first molten MR. MALONEY: Through the peephole? - about two to three minutes. But we have left our iron soak for an hour to an hour and a half; it is almost ready to go when we put the blast on. TlR. LOIJCHTEN: Don't you think the amount of steel in your mix has something to do with that? MR. MALONEY: That would he a day when we had no steel. MR. DOUGHTEN: The more steel you have, I figure, the shorter time it should soak. That is if you are working for a low carbon iron, you have more possibility of the steel taking on carbon. CHAIRMAN GREENSTREET: Mr. Newland, how long before you see the first molten iron? MR. NELAND: Usually about seven or eight minutes; sometimes I have seen it ahead of that. CHAIRMAN GREENSTREET: Did you get into any trouble before the end of the heat?

22 MR. NEWLAND: Not a bit. CHkIPMAN GREENSTREET: You don't think that you lowered your bed by that extra dropping there so soon? MR. NTEWLAND: No. When I saw it through the portholes, I saw it was dropping rather rapidly, and I knew it was accumulating in the bed. As you are aware, and foundryrnen here are aware, years ago lots of them used to blow it through the front and try and gauge it that way; wait until it was running freely, and gauge the time that way. Most of the places today are backing it up with white sand or something of that kind, and judging the time from the time it was dropping. If we say we are getting it running over the spout, say eight or ten or seven minutes, well, that is bringing in another question again, -- how much metal are you allowing to come up in there. You could have it running freely in seven or eight minutes out of your front spout, whether it was low carbon iron or a big percentage of steel. I have seen as much as 97% steel put in a cupola and it would just come down at approximately the same time, as gray iron. CHAIIMAN GPEENSTREET: Do you think there is any advantage in waiting a little bit longer for it, particularly if you are going to run a long time? Do you think that the iron, in starting to melt in three minutes, is melted at a little bit lower place than you would like to have it melted? tuyeres. MR. NEWLAND: Yes, I think you are melting too close to your CHAIRMAN GREENSTREET: And you might, if you have got a little extra coke on your charges beyond that, it will probably replace that bed and won't give you any bad effects. But supposing that you had a low bed, and you were running steel on first and wanted a low carbon iron, and your bed was fairly low, and you got a quick melt in the beginning; in that case, would you think, that you should use a little more coke between charges for safety? MR. NEWLAND: Yes. If it was showing in as low as three minutes I would expect that I was coming down too near to my tuyeres and if I was running that say for an hour longer, I would expect to see the tuyeres all blackened up, as Mr. Benkert has said. In different parts of the country, we are getting back to this 1 to 4 ratio, or 1 to and I agree with (Mr. Titgen). It comes back to your tuyere ratio again; 1 to 4 or 1 to 4, and velocity, pressure, generally, and the nature of your coke. But if you are coming down to three minutes, I don't care whether you are melting gray iron, stove plate or what it is, you usually find when you look at your cupola in the morning, it Is pretty nearly burning out, the top plate of your tuyeres. And I prefer to see it coming down in about 7 minutes dropping freely all over the cupola. I always feel I am getting much better iron. CHAIRMAN GREENSTPEET: The reason I asked that question, I had an opportunity one time to prove that point, and you can prove a lot of things running chilled iron, if you are pouring test pieces from every tap, that you ou.ldn't possibly prove on gray iron. While the same thing takes place, it isn't so apparent; you can't measure it so well. We poured a test piece from

23 every tap, or about every ten car wheels. (We were running car wheels at the time) and where we were tapping into a big eight or ten ton mixing ladle we found the first iron was always soft, that the test pieces had less chill on them than the other test pieces. It was taking about nine minutes for the first iron to show. We started lowering that bed gradually every day, until we got the first test piece the way we wanted it, as we had been getting the others. But we didn't change the amount of coke between charges. Consequently, before we had gone an hour or hour and a half, we commenced to get too much chill on the other pieces, so we decided to keep the bed at that point and be very careful not to burn it too much, so that we would always be sure we didn't get it too low, and increase the coke a little bit on the other charges, and then we got it uniform throughout. It used to be a common practice in the car wheel industry, that the first iron was always softer than the others, and because they had to run a long heat, they figured that they had to be safe and must carry a little higher bed to carry them over. Once it was started, it wasn't there though, so I traveled on the assumption we ought to lower the bed to the proper height and maintain it throughout the day. In order to do that, they all bragged about how little coke they used between charges, but nobody said anything about how much they used on the bed. They had to have that anyway because that was the starting point. But by lowering the bed coke and increasing a little more coke on the other charges, we were able to run uniform test piece after uniform test piece, tap after tap, all day long. I asked you that question, because it looks to me like it raises a question if the iron melts too quickly, especially if you get it considerably quicker today than you did yesterday, (provided the weather is the same). I used to laugh at a man who said the weather had anything to do with it, but when you consider the difference in moisture between Denver and Boston, you commence to think about it-- The different amount of oxygen you are putting in with this air. I think therefore that the quicker you can get your first iron and have it hot, naturally, the better you are off, provided you don't get too little coke on the other charges. A lot of people will tell you, "Well, I am only melting ten to one", or "eleven to one", or "nine to one", as the case may be. They are talking about between charges, and not about what they are putting on the bed. They have probably got the bed twelve inches higher than they should have it. How long do you wait on stove plate, Mr. Schaal? I like to ask you a lot of questions because many of us don't melt stove plate, and we may some day get into that line of work and get different conditions. R. SCHAAL: The first iron appears at the tuyeres between six and seven minutes. CHAIRMAN GHEENSTEET: I think that is pretty safe myself. I would rather have it there at that time, about six or seven, than at three or four minutes. You are not taking chances, and on stove plate there is one thing you have to do, that is to make soft iron and some of the hardest iron I ever saw in my life came out of a stove foundry. It was absolutely white, because they had simply got it too close, and had too much air in it. How high is your coke bed above your tuyeres?

24 MR. SCRAAL 28 inches. CHAIRMAN GREENSTBEET: You have lower tuyeres? MR. SCHAkL: We have two rows of tuyeres. CHAIRMAN GREENSTPEET: That's right; you have upper tuyeres and you are working 28 inches above. And do you use by-product coke? MR. SCHAAL: We use a mixture of C-rayston and by-product, whichever will burn the fastest. CHAIRMAN GPEESTREET: Well, now we come to charges and charging. This is a big thing to cover. "V. Charges and Charging: All materials should be carefully weighed and loaded systematically according to size of pieces and composition. The proper system is best determined by experiment and practice. It is good practice to charge the heavy pieces around the lining of the cupola. This has a tendency to promote a better blast penetration. Under ordinary conditions, the charges should be 2000 to 3000 lbs., and all alike. The charging may be done either by hand or by mechanical equipment of proper design. It is not the best practice to use mixtures of widely different compositions in the same heat." (I think that is a thing pretty hard to govern. Sometimes we ought to have about twenty different mixtures, but we try to hold it down as low as we can.) "When this is necessary, separation of the mixtures may be partly accomplished by using an extra charge of coke at the point of separation." You have got to remember when you do that that you are throwing everything out of balance,-;hen you throw the extra coke on, but there may be times v.--hen it is necessary to do it. I don't believe there is much chance for argument on that point. It doesn't say a whole lot about it, except to try to stay away from a lot of different mixtures as much as you can. "VI. Flux. A good grade of limestone should be used. For long heats and continuous melting, limestone amounting to from 2 to 4 per cent of the weight of the iron charge, and 4 to 5 lbs. of fluorspar, should be used on each charge." Now there isn't anything in that paragraph to tell you what to do with short heats, but it does say for long heats and continuous melting. imagine everybody uses some kind of a flux

25 MR. DOLtHTEN: Would it be in order to raise a question of the size of limestone? CHAIRMAN GREENSTBEET: It hasn't been mentioned, and I think it is a good point. I have seen some people use pieces, half to an inch, and I have seen otheis throw it in three or four in diameter. I used to be prejudiced against using big pieces myself, but I now think the heat cracks it up by the time it gets down to the melting zone, where it does the real fluxing, and I doubt if it makes much difference, as long as you don't get it too small, But if anybody else doesn't agree, se would like to hear from him. MR. NKRT: You are bound to get an evener distribution if you have small pieces, with the same amount of weight. CHAIRMAN G-REENSTREET: When you throw it in the charging door, it starts to crack and bursts all to pieces. MR. BENRT: Do you mean oyster shells? CHAIRMAN GREENSTRT: I mean even limestone, when it is too big. Of course, it won't shoot like oyster shells do; they shoot around like firecrackers. But it does sort of crack and disintegrate when it goes down. MR. COPPAGE: Would you be satisfied to have your purchasing agent ordering a carload of limestone, specify "One carload of good grade limestone"? CHAIRMAN GREENSTREET: No, I wouldn't. Mr. Doughton, what are your specifications on a good grade of limestone? MR. DOTJGHT\T: We buy our limestone by specification. I think it is what we call Wo limestone. CHAIRMAN GREENSTREET: That is your specificaticn, Mr. Schaal? MR. SCHAAL: The only specification that we have, it must equal or exceed 96% Ca03. As far as the size of the limestone is concerned, I am inclined to agree with you that as longas it isn't too small, it makes no difference. And the gentleman here who was remarking about even distribution over the charge, it certainly is not good practice to try to distribute it evenly over the charge; it will distribute itself by the time it gets down. It is a lot better to put it in the center. CHAIRMAN GREENSTREET: Keep it away from the lining as much as you can. We do; we try to throw it in the center. It gets down there without giving ycur lining much trouble. I have seen people that have actually thrown it around the lining, and don't believe they knew why they did it. But you see a lot of things when you go in other people's foundries and you come back home and think you are not auite so bad off as you thought you were. I have, sometimes, and I guess the rest of you have, too. MR. COPPAGE: I would like to go back just a little, Mr. Greenstreet. I had a fellow put forth an idea that the thickness or size of scrap you put in the cupola ought to compare with the thickness of the metal in the castings that you are pouring, and that article calls for large pieces on the side. It seems to me the chemical analysis of your scrap originally would more or less

26 compare with what you are trying to get in your casting, and that wasn't a bad idea, that if you are pouring half inch stuff, something of that sort, to use scrap around that thickness, and if you are pouring heavy castings, from 2 inches up, then you can use heavier scrap. I was wondering what your opinion on that would be. CIRMAN GPSTRT: Supposing that we are undertaking to make agricultural machinery. I would like to have all scrap agricultural machinery if I could, because I would have it more nearly the analysis that I was looking for in the finished casting. But if I bought up a lot of gears and heavy machinery, the chances are the analysis in that scrap would be so far different from what I wanted to get that it would be almost impossible for me to figure the analysis of the scrap that went into the charge. Consequently, I would be apt to wake up tomorrow and find out the analysis of my casting was probably 25 to 50 points lower in silicon. I think that is what the man meant; at least that is That I tried to take out of it, that you certainly wouldn't want to charge car wheels, no matter how small they were broken, in a cupola to make bathtubs, radiators and stove plate. Some people say, "that is wonderful looking scrap". Of course it looks wonderful; nice and open and everything else, but it took longer to cool, and in that particular casting, the chances are you would have a high percentage of graphitic carbon. Once you melted it and poured it into a light casting you might find that you had a very high percentage of combined carbon, and not so much graphitic as you wanted, if you were looking for soft castings, and that would carry you through on pretty nearly anything else. Suppose, for instance, you were making car wheels, and bought agricultural scrap and put it in them. If you assume that was just returned scrap you found, car wheel scrap, you would be all off again. But I think if a man wants to use heavy scrap, even in making heavy castings, that he ought to have it broken as small as he can get it, and consider that the analysis in it is just about what he wants in his finished casting. MR. DOUGHTEN: We try to buy textile machinery, running our small work first. On the succeeding charges, half of the scrap is good sized pieces and the other half small pieces, hoping in that way to get a good average. CHAIRMAN GREENSTREET: A lot of things in a cupola are averaged. A man just has to use the best common sense he has. We are always very fussy about our scrap, because we use a lot of it. A fellol asked me the other day, when I was trying to get some business from him, "I understand you fellows use a lot of scrap". I said, "We do; we use more scrap than anybody in Philadelphia". "That's bad", he said, "I'm afraid we ought not to buy castings from you". "Well", I said, "maybe not, but if your castings are strong and machine all right, we think it is our job to know how to mix the iron. We use all our own r turned scrap, plus all the bad castings we have, (which are quite a few) and then we try to get back all the castings, spoilage from our customers, knowing that we made that and we can pretty near gauge what it is. Also we buy scrap from the scrapyard, and watch it very closely. The scrap dealers will often slip something over, but we try to get scrap that is not too heavy." If I want to close it up, I will either use some car wheels or steel on the first charge. We run our harder castings in the first part of the heat, and probably anywhere from 18,000 to 24,000, sometimes 30,000 pounds of 1% silicon, from that on down to 200. To keep those returns separated, causes a

27 lot of grief. In the selection of a car coming in, you can reject that; but you always have the return scrap with you. We try to buy low sulphur coke, and to use as little pig iron as we can, because there is a difference now between pig iron and scrap of about $8.00 a ton, and if you can make good castings out of scrap, rather than pig iron, we think it is economy. We have always got to watch never to sacrifice quality, and I know perfectly well that ninety foundrymen out of a hundred say, "Well, you can't make good castings out of scrap". But you must remember that if you take a test bar poured from a blast furnace and find a certain strength, and you put that same pig iron from which the test bar was poured through a cupola and pour another test bar, you get a great deal stronger test bar, But I think the trouble from melting scrap in a cupola, is that the chemical analysis of mixture, is not changed and the same analysis in the casting is not obtained as formerly when pig iron, was used. We use about % scrap. Test bars are stronger, mixtures are a lot cheaper, and the castings turn out good, or we wouldn't sell them. When you are using that much scrap you have to select a lot closer than when you use pig iron. Our sulphur is considerably under 12%. We supply additional manganese, and take care of our silicon, and our carbon runs about 3% total, in ordinary machine castings, like hangers, bearing boxes, and casting of that kind. We don't use this in our pressure work; we use semisteel. But we go as high as 30% car wheel, 10% steel, and quite a little machinery scrap so we are only running about 35% pig iron in the mixture, getting a test bar that pulls better than 30,000 pounds per sq. in. We don't attempt to make the so-called high test iron. Some fellow says he wants nickel chromium iron; I say, "All right, how much shall I put in?" He tells me that, and I figure it out and charge him for it. Now I don't mean to say that nickel chromium iron or high test iron isn't a good commercial article, or isn't a good iron. But you can only do so many things in one foundry, and we would rather recommend that to the fellow who makes a specialty of it. We are now running three to four mixtures a day, and in one cupola that is one or two too many. MR. COPPAGE (Pusey & Jones): Did I understand you to say that you could give a man just as good iron without the nickel and chromium, if he put it up to you? CHAIRMAN CREENSTREET: No, I didn't say that. (Laughter) I said we don't attempt to make nickel chromium iron because we have got too many other mixtures to make now, and we would rather recommend him to somebody that makes the so-called high test iron. However, if he insists, we put nickel or chromium in; and ask him how much he wants. MR. COPP.AQ.E: That is all right. I agree with you. CHAIRMAN GREENSTREET: (Returning to recommendations): "VII. Blast; The amount or volume of air required depends on the desired rate of melting, coke ratio and quality of coke. It is generally assumed that 30,000 cubic feet of air is required per ton of iron melted." All my life, I have wondered where that figure came from. Does anybody Imow? Mr. Titgen, do you know why they use 30,000 cubic feet of air

28 to melt a ton of iron in an hour? MR. HARRY TITCEN (Titgen.-Eastwood Co.): As far as I know, that was based on 72-hour coke, years ago, furnace coke, the amount of carbon, determined the amount of oxygen required. Nov', since we have got into by.- product coke, lots of iron is melted with 23,000 instead of 30,000. CHAIRMAN GREENSTREET: I looked that up one time. David McLaine made a statement that iron ought to be melted at one pound coke, ten pounds or iron, and I wondered why, and how he arrived at that conclusion. After making a lot of investigations, searching through a lot of literature, I discovered to my surprise that it was based on coke being pure carbon, which it is not. I have never been able to find out why it should be 30,000 Cu. ft. of air, and I assumed that perhaps was based on coke being pure carbon. You are trying to put oxygen into that cupola to combine with the fuel and make complete combustion. If it takes 30,000 cubic feet of air to give you a cer - tain amount of oxygen, well and good. But if you can get the same amount of oxygen with 20,000 feet of air, or with 36,000 cubic feet of air, which is going in the other direction, it looks to me like that is the thing to figure on, -- the oxygen, rather than the cubic feet of air. You go out to Denver, where it is awfully dry, and then come back to Boston where it is awfully damp, and you may get the measurement all right, the same as you do on a gas meter flowing through your house, but you have got an awful lot of air behind that gas; you are measuring the air just as well as your gas. Of course, if you are using coal, and you put 30,000 cubic feet of air in, you won't melt a ton of iron per hour. If you are using Grayston coke, Potter coke, or some other soft coke, probably it will melt more than that for a while. But if you continue to shoot that much air Into that soft coke, the chances are that you will melt a great deal less before you are through. WR. EDABD BENEERT (Fairmount Foundry Co.): the pig iron and scrap have a lot to do with that? Wouldn't the size of CHAILkN GREENSTREET: Of course it would have something to do with penetration. But I am trying to bring out, that you shouldn't put any more air in the cupola than you can possibly get away from, because it is an utter impossibility to melt iron without oxidizing it to some extent. The method that is used of blowing the air, the ozygen, into that iron has a tendency to oxidize i -b. In that connection, it is a good plan to remember that you can't sell oxidized castings, unless you de-oxidize them. Now, the less oxidizing you do, the less de-oxidizing you have to do. The steel people de-oxidize with manganese or spiegeleisen. The only reason I spoke of this was that I think that that thing is liable to lead you a little bit wrong. If you can melt your iron fast and hot and maintain your strength, -- as you say, it is awfully hard to tell that on ordinary gray iron, but on chilled work it shows up awfully fast because the depth of your chill will pretty nearly tell you what you are doing to it. George Evans ran some experiments sometime ago to determine about oxidizing iron. I have had several talks with him since, and found out a lot about it. Of course, he only hit the high places when he spoke before our Association, but he did tell me all the steps that he took, and what he discovered. Among other things, he determined that it wasn't safe on specification work to have a distance of less than fourteen inches between the bottom of the tuyeres and sand bottom, for that very reason. Many stove plate people and many others,

29 radiator people, even car wheel people, since Evans left Griffin, have gone back to that to get the tuyeres as close as they possibly could. But they are using soda ash in the ladle. That may help; I don't know. I think soda ash or purite does a lot of things I don't understand, not being a chemist. But I have determined this, put Purite into a ladle, and you see a tremendous boiling effect and a lot of slag comes up from it. Here is a ladle you haven't doped at all. I mean a certain proportion of Purite. You pour both of them, and analyze them, and you haven't killed your sulphur at all. But add a little more purite and it will cut out a lot of the sulphur. I think when that boiling took place, it did something besides cut sulphur, because up to that point it hadn't done it. Maybe the addition of soda ash in the ladle does some of dc-oxidizing. I am not sure, because as I say, I am not a chemist. But it might be possible that they are able to get away with a low hearth without having weak wheels with the low tuyeres that they weren't able to do when Evans made his experiment before he started using soda ash. He used a lot of soda ash while with Griffin, but it was after he determined fourteen inches was as low as he could go, and never attempting to go lower. But since he left, they have dropped it down to six inches to save that coke on the bed. Has anybody anything to say whether they think 30,000 cubic feet of air to melt a ton of iron per hour is too much? MR. SCHAAL: Mr. Greenstreet, I think that is just another one of these variable factors like the size of 'tuyeres I spoke about a while ago. You can't lay it down and say 30,000 cubic feet of air. I don't think that that article presumes that it can say that. It simply says there, "it is generally accepted". That may be a good average, but it certainly shouldn't lead anybody to believe that that was the proper figure at all, because it very seldom is right on 30,000. dhkipj\w GREE'NSTREET: I think you are right, Mr. Schaal; but I do believe that some people have taken that as gospel truth. I know I did, once. I couldn't cut the blower down. I set it at that, and said I wanted it, and couldn't reduce it when I wanted to. MR. SHAAL: If anybody would start to figure how much air it would take to melt a ton of iron, they would have some job on their hands; and not only that, but after they got all the calculations made, it wouldn't tell them a darned thing, because they wouldn't know what the efficiencyof their cupola was to begin v:i'th, and that is the biggest factor in the whole business. MR. DOUGH'rEN (Pusey & Jones): I think, Mr. Greenstreet, very few foundries running a positive blower know how much they are getting. I think we all fall down in making a periodic survey of our blower impellors pipe leakage, and so forth. We read the volume meter and take that for the truth. CHAIRMAN GPEENSTPEET: "The blast pressure varies according to style and size of tuyere openings, height of stack and size of coke and metal used in the charge. The pressure may vary from 6 ounces to 24 ounces, depending on the above conditions. "For uniform melting, the volume should be kept constant and the pressure allowed to vary. Every cupola should be equipped with volume and pressure gages and a means of adjusting the amount of air delivered into the wind box."

30 Does anybody have anything to say while we are on the wind box, whether it makes any difference about the size of the wind box as to tuyere opening? Did you find that it made any difference, Mr. Schaal, whether your wind box was three times as big as some other fellow's? MR. SCHkA.L: I don't know enough about it, really, to talk authoritatively on it. It would make a difference within large limits, but within reasonable limits, it oughtn't make any. CHAIRMAN GEENSTHET: What do you think, Mr. Titgen, regarding the size of your wind box as to tuyere opening? MR. HARRY TITGiN: We have always found we get better melting and hotter iron with a wind box that is at least ten to one of your tuyeres. Now some people just put a bustle pipe around. But when you put a wind box on the outside of that shell, you can picture the air in this wind box as water, and have the two inlets there; you have a volume of air all around this belt that is giving an equal distribution to each one of the tuyere openings, and when you have a bustle pipe arrangement to feed those tuyeres, your air is of a higher velocity. I know of a case not far away, where one foundry is getting 17 to 18 tons per hour with the bustle type and so-called elbow tuyere, continuous melt, and the other foundry is averaging 21 to 22 with the wind box in. CHAIRMAN GREENSTREET: Do you mean the one with the larger wind box gets a faster melt MR. TITGEN: Yes, because you get a more equal distribution of the air through your tuyeres, and your pressure on each tuyere is about the same. CHAIRMAN GREENSTREET: Do you think if they changed their coke ratio, the size of the charge, or anything else, it might defeat that condition? -- That is, that they might be able to do as well with the smaller one as with the larger one? MR. TITGEN: There would be some change, but not that much. CHAIRMAN GPESTRET: Do you think, contrary to everything that has been said, if they had less tuyeres on the bustle pipe, it might change the condition? MR. TITGEIN: No. MR. BENKERT: On a. blast pressure of 6 to 24 ounces, -- I think anybody that cares about their power bill it will make a lot of differences. 6 to 24 ounces is a lot of difference. CHAIRMAN GPEENSTREET: In order to get air in there you may not be able to get away from 24 ounces. That is why I have always believed it was a fallacy to use too little coke. If you use a little more coke, you probably won't create so much pressure, but if you are working on the ragged edge, you probably will

31 MR. BENKRT: We had our pressure around eight and one half ounces, and getting up to twelve ounces, we can't keep any fuses in our motors. CHIR'iAN GREENSTPEET: Try a little more coke tomorrow and probably it won't do that. Most people are trying to make a reputation for melting iron with very little coke, and some of them like to say they melt ten or twelve to one or nine to one. But if all the facts were known, you would find a lot more melting seven to one. Some people tell you that honestly, they don't really know; they haven't been on the platform and measured it for weeks, maybe months; just as this gentleman said about checking up your leakage in your pipes, and so on. How many men check the cupola man? They are afraid he will get insuited. MR. BENKERT: I mean 6 to 24 ounces is a lot of difference, on the same size cupola. CHAIRMAN GREEMSTREET: I agree, it shows bad practice if you can't control it any better than that, and I would say if you were running efficiently you would use less pressure, with the same tuyere area that is recommended. It recommends this tuyere, and says it should be 6 to 24 ounces, a wide spread. MR. BENKERT: If you had a 30 horsepower motor running for a 54-incb cupola, and were running along about nine ounces pressure, and your tuyeres would get blocked, or your blower didn't work quite right, your pressure would build up to 24 ounces. That motor wouldn't keep going. CHLIPMAN GREENSTRET: I don't think you would keep going long anyhow. That would build up so high you wouldn't be able to get any air in it. But they do it. I don't think it is a good recommendation. MR. BENKERT: I think the motor would stop. CHAIRMAN GREENSTREET: I think 24 ounces is entirely too much. I worked for a man one time who tried to regulate the chill on his wheels by the blast, and he thought it was all right, but nobody else did. But if his wheels didn't show quite enough chill, he simply gave it a few more turns, and if they showed too much chill, he cut it down a little bit. But that was wrong. However, people do it. They do lots of foolish things. From 6 to 24 ounces is too much variation, I think. I saw a cupola lined 86-inches that worked on four ounces very nicely. Of course, in that case you get a very soft iron from a given mixture. That is why I say you can really improve iron putting it through a cupola. But he got it softer than he wanted, because his blast pressure was low. He had it soaking in there and running on down. The reason he did that was because his cupola was too big for his present melt and he expected to do more later. So he just ran along. One time down at Baltimore, at Flynn & Emerich's, we had a cupola I think was probably built before I was born, and whatever is right today, that was wrong. But if that is right, then everything else is wrong. But this wind belt went around the back of the cupola and stopped and was plugged up on each end in front of the tap hole. It was a small cupola, lined at 39 inches. That is an odd size, too. They probably built it themselves. But the wind belt didn't go all the way around, it was a sort of bustle type, except it was made square and bolted on. And we had considerably less air than we needed, and we undertook to melt iron in it. They said it couldn't be done. But they only