Патент USA US2384349код для вставки
Sept. 4, 1945. D. w. SHERMAN ' FORGING DIE ‘ _ 2,384,349 ' Filed Jan. 27, 1944 , ' ‘F161.’ 2 Donald W Sherman INVENTOR. >BY V ATTORNE1’. P 42 some . wlsnen'nm, FQRGINGDIE .',2,:s4,:'49 Shorew'ootLWlaJsslgniuto _ ' . 1,. _ . O. Smith Corporation, Milwaukee, corporation of New York _ ' ., H. v P , ' Application January 27, 1944, Serial No. 519,930“ I ' 5Clalms.. This invention relates to forging dies. The principal object of the invention is .to pro vide a forging die for high temperature forging (cue-so) " ' - H " ' then firing the were about?‘ 16006 ‘e. The m- . ing operation fuses the enameling. material and bonds the same to the steel lining 4 throughout. The upper die I is of similar construction with a lining ‘I and ceramic enamel coating 0. The According to the invention, the working sur face of the upper die I, however, is usually of face of the die or of a thin liner therefor has a different shape than that of the lower die i, de-_ coating of ceramic enamel or the like bonded pending upon the shape of the piece to be formed. thereto to serve as a lubricant. ' In carrying out the forging operation, the bar The invention has been applied to the forging 10 9 to be forged is ?rst heated thoroughly to above of thin sections in one forging operation as set 2400° F. and then subjected to the forging pres forth in applicant's copending application, Serial sure of the two opposed dies l and '6. In the forg No. 519,940, filed on even' date herewith for ing operation the bar I is first engaged by the Method of forging and lubricant therefor. dies along the center line of the latter, and as An embodiment of the invention is illustrated 15 the metal of‘ the bar ?ows laterally under the in the accompanying drawing in which: pressure of the dies thereon, it progressively en “Figure 1 is a plan view of the face of a forging gages more and more of the die faces until it sub stantially ?lls the die cavity and takes on the Pig. 2 is an enlarged transverse section of the shape of the ?nished forged article. : ' die taken on line 2—2 of Fig. 1, together with 20 The ceramic enamel I and I bonded to the its mate; working faces of the lining becomes plastic from Fig. 3 is an enlarged fragmentary section simi the heat of the forging blank 0 and serves as a lu lar to Fig. 2; and bricant for the dies. It was found in tests that Fig. 4 is a similar transverse section showing a without the enamel it took about 1,800 tons pres modi?ed construction of die without employing sure to form the forged product described: where and in which a lubricant is secured to the work ing face of the die. ' a replaceable lining. as with the enamel lubricant it took less than 200 The dies illustrated in the drawing were con tons of pressure. The softening of the enamel structed for the forging of a specially shaped occurs progressively as the metal being forged steel plate having thin sections of considerable gradually ?ows laterally in the dies, and therefore 30 surface area. The plate is forged from a round a fresh supply of lubricant is always being sup_ bar about three inches in diameter and several plied at the point of ?ow of the metal. The bond feet long in a single operation of the forging ing of the enamel to the working surface of the press. In order to accomplish this, and in ac die prevents its being scraped off or pushed ahead cordance with the method set forth in the co of the ?owing metal. , 35 pending application above speci?ed, the bar is The enamel coating should be at least ten thou heated to swim; close to the melting point of ~ sandths of an inch thick and preferably compris the steel and a ceramic enamel lubricant is em es two or more coatings, one applied on another. ployed to line the dies. The ?rst coat should be of a composition giving The present invention is directed to the con good bonding characteristics. The enamel is struction of the dies and the application of the preferably of the hard or glass type ?ring at above ceramic enamel lubricant thereto to obtain the 1600“ F. as distinguished from softer types ?ring most satisfactory forging results. as low as 1300" 13‘. However, this may depend up The lower die I constitutes a block of metal 2 on the shape and composition of the article being having a face 0 generally shaped according to forged and the forging temperature employed. the article being forged and provided with a 45 As explained in the copending application re relatively thin replaceable lining of sheet metal ferred to, the spread between the ?ring tempera 4, and the latter has bonded to its working face ture of the enamel and the temperature to which a continuous enamel l. uniform coating of ceramic the work blank is heated for forging should be such as to effect a heating of the hard enamel to The lining 4 may be formed directly against 50 a plastic state to provide its lubricant effect. If the face I of the block 2 sons to fit tightly and the enamel remains too hard, it may obi ectlonably affect the surface of the forging. 0n the other The enamel I is applied to the working face hand, if the enamel melts to a liquid state too soon of the lining by ?rst spraying a vitreous enamel it may be scraped off and thereby fail to lubricate. ing material over the surface to be coated and 65 In the modi?ed embodiment of the invention uniformly thereagainst. 2,884,849 2. Adieformetalforgingcpuationscomvrh illustrated in Fig. 4, the enamel II is bonded di reetlytotheworkingfaeesofthedles II and II ingadiememberhavingaworkingfaceforamp ingaheatedmetalarticleandahsrdrefracton which are dimensioned to shape the article with lubricantwhichsottmsundertheheatofthe out a liner. In employing this embodiment, the ?lorgingoperationliningtheworkingfaceof?ie working face of the die is cleaned between each one or two forging operations and then reenam e. eled. In the preferred embodiment of Figs. 1, 2 and 3, however, the liner is su?lciently cheap to permit it to be discarded and a new enameled liner placedinthedieassoonastheenamelhasbe 10 come sumciently destroyed to prevent its use. It is usually best to use the enamel only once and to replace the liner between each forging opera tion. It is also possible to clean and reenamel the liners for repeated use. Various embodiments of the invention may be employed within the scope of the accompanying claims. The invention is claimed as follows: 1. A die for forging operations comprising a die go member having a working face for shaping an article, and a coating thereon of ceramic enamel bonded thereto. 3. Adieformetalforgingopmtionscomprb ingadieblochasheetmetallinerforthersceoi thedieblockandprovidingaworkingfacefor thedie,andaceramieenamelcoatingcovering sugidworkingfaceandbmidcdtosaldsheetmetal er. 4. Inadieforhightemperaturemetalforging operations,areplsceablemetallininghavingits working surface coated with a vitreous material ?redandbondedthereto. 5. In a die for high temperature metal forsinc operations, a glass enamel lubricant coating and bondedto the working surface of the die. DONALD W. SHERMAN.