US1018363A - Manufacture of chains. - Google Patents

Description

UNITED srnrns FATE WINFIELD S. POTTER, OF NEW YD'R'K, N. Y., ASSIGNOR T0 ALLOY STEEL FORGING': COMPANY, OF WIIMINGTON, IDELAVVARE, A CORPORATIQN OF DELAWAILE.

MANUFACTURE or creams.

No Drawing.

Specification 6r Letters Eatent.

Patented Feb. 2t), 1912.

Application filed December 16, 1911. Serial No.- 666,235.

the following to be afull, clear, and exact description of the invention, such. as will enable others skilled in the art to which it appertains to make and'use the same.

My'invention relates to the manufacture of chains as,-for'instance, chains'consisting of the ordinary interldcked round sect-ion oval links.

It has for its object the production of a chain of manganese steel .whose links have throughout a strength and capacity to resist shocks and strains substantially equal to the metal in the original unbroken bar or shape from which the links are formed.

It also relates, generally, to the welding of manganese steel.

It is particularly the purpose and object of my invention to avoid the separations, segregations, and irregular or coarse recrystallizations, with their consequent weaken-v ing of and injury to the high carbon manganese steel suitable for the purpose, which" occur when a wrought bar or other blank shape of such steel is reheated to a high tem perature, after the original forming of said bar or blank shape, during the welding operation. i p

' In the practice of my invention, the-rod or other blank shape from which the chain is to be formed (hereinafter referred to as the bar), is suitably produced by heating a manganese steel billet preferably to about 117 5 C. to 1200 (3., rolling the billet to the section of link intended, and completing the working of the metal during the forming of the bar at a finishing heat below 1075 C.

If, after leaving the finishing pass of the mill the bars areto be air-cooled before the next succeeding step of the operation, the

finishing heat of rolling ,should be in the neighborhood of 1075" G. for small bars which cool quickly in the air, andproportionately less for large bars, as, for-example, the temperature in the last pass of the rolls should be about 800 C. to 950 C. for bars of 2 inches thickness. A bar of any required size for chain-making may be finished at temperatures between 800 and IOT5 0.,

. with goodresults, it immediately quenched in water. With thin bars, the cutting andforming-into open links prior to the welding operation may sometimes be done. cold, but it will usually be found more suitable to bring the links to form by cutting the. bar into pieces, bending and interlocking the pieces of the "intended chain at tempera tures between 350C. and 1025 C., according to the size of the bar. That is to say, at

the time of its conversion into chain, the rolled bar should preferably have a temperature within the {range of 350 C. to 1025 (1, andusually 97 5 C. or closely approximating that temperature. It is then delivered to and speedily passed through-the bar cutting, linlcforming and link-interlocking mechanism.

The rolled bar may be supplied to the chain-forming mechanism, hot from the heat of forming, or after-having been reheated to the appropriate temperature. To maintain the temperature of 'the rolled bar after it leaves the forming rolls, it may be introduced as it issues from the forming rolls into a hot furnace compartment, or other heater, having at the time of entry of the hot rolled bar a temperature preferably of about 975 C. Or, if the bar has been permitted to cool and requires reheating, it is restored to substantially the same temper ature with which it left the rolls, by rapidly reheating it, thatis to say, by reheatmg it during a time too short to permit the metal to recrystallize in any ob ectionable way. In any event, the bar is subjected to the cutting, linlnforming and link-interlocking action of the chain-forming mecha nism and otherwise prepared for welding, and, as hereinbefore indicated is supplied to the chaimforming mechanism, eithercold, or hot from the heat of forming, or after it has been cooled and subsequently reheated.

The welding may be accomplished. by causing an electric current to flow between the surfaces to be welded while these surfaces are forcibly pressed together. The pressure applied at the Weldis. continued after the metal has been caused to flow and after the desired weld has been produced, in order to compensate for the weakening tendency of the high temperatures incident to the welding operation at or in the neighborhood of the weld. This continued appli-' cation of. force and pressure tends to sun tliiii press and a'void the and undesirable metal udyoinin the we l the portions or t c link highly heated dun ing the welding ope tion will be brought.

la to a condensed LU-(l a very fine-grained condition throughout. bonsequently, as the welded chain issues .iflOllltllG forging or pro mg; mechanism, it consists of links which fully rctain throughout their entire h, i ludii the weld, all of the useful ects of the and compression produced by the rolls in forming the billet into the rolled. l fact, at the surfaces where the links ha e been welded the metal is ei'en still further compressed and improved by the force and pressure applied during; the forging operation.

To illustrate typical instance of the practice ct thv invention, it will be assumed that the metal to be formed into a chain is manganese steel having in its composition carbon approximately 1.20 per cent., manganese 12 per cent. A billet of this metal is heated to about 1175 C). throughout and is rolled, for example, to a round-bar of the di 'ucter or the section of a link of the intended chain. The bar is caused to issue from the rolls a temperature between 000 C. and 1075 C. (preferably 975 C.) is thereupon quickly introduced into the ei-which will hare about the same length ,bur and wherein about the same temture will be maintained. In order to avoid material loss of heat by the bar any change in the condition or structure of its steel, the is then delivered from the heater and through the chainforming and weldij mechanism in such manner that. the c ing oil into link-lengths, the forming, of the links, the welding or" the links, the forging ot the welded bortions and the final issuance of the welded chain from the chain-formingand welding mechanism is accomplished rapidly so that the completed chain has as nearly as possible the same tcmperatiue that the bar has on leaving the rolls. Local inequalities or une enness in the temperature of the finished chain maybe compensated and equalized by a short heatingoperation at about 3300 C. to l0l'5 The chain is then quickly cooled by immersion in water, or the finished. chain may be otherwise rapidly cooled to a temperature below 420 (l. Or, after weld ing and pressing the links, they may be reheated to about 075 1). to 1025 0., reworked at the welds, and then quenched or otherwise ra iiidly cooled.

in order to avoid the occlusion of slag or other foreign matter in the weld, the cuttins: of the bar into lengths is preferably so executed that the surfaces which are to meet and by their 'tlow form the central portion of the intended weld project beyond the remainder of thesurtaces to be welded; so that, when the welding heat and the pressure is applied, the weld occurs first at the center and then progressively outwardly toward. the edges until the weld. is complete.

What I claim is:

1. T he method 01 producing wrought manganese steel chain, which consists in cutting a bar of manganese steel into pieces suitable for links; bending and interlocking the pieces and. electrically welding their ends to form links; thoroughly working the welded portions at temperatures below 1075 (3.; heating the links to about 1000 (3.; and rapidly cooling to below 420 6.; substantially as described.

2. 'lhe method of producing wrought manganese steel chain, which consists in heating a bar of manganese steel to between 350 C. and 1075 (1.; cutting the bar into pieces suitable for links; bendingand interlocking the pieces and electrically welding their ends to form links; thoroughly working the welded portions at temperatures be low 1075 C.; heating the links to about 1000 C.; and rapidly cooling to below 420 C." substantially as described.

3. The method of producing wrought manganese steel chain, which consists in heating a bar of manganese steel to between 350 C. and 1075 0.; cutting t-hcbar into pieces suitable for links; forming and inter locking the pieces and electrically welding their ends to form links; thoroughly working the welded portions at temperatures between 800 C. and 1075 0.; heating the links to about 1000 C; and rapidly cooling to below 420 (1; substantially as described. l. The method of producing wrought manganese steel chain, which consists in heating a manganese steel billet to about 11 75 (l; rolling the billet to bar form with a finishing temperature below 1075 (1.; cutting the bar into pieces while still hot from the heat of rolling; bending and interlockingthe pieces and electrically welding their ends to form links; thoroughly working the welds at temperatures between 800 C. and 1075 (1.; equalizing the temperatures in the links at about 1000 (1.; and rapidly cooling; to below 420 0.; substantially as described.

5.-The method of welding, working and heating manganese steel, which comprises bringing the ends to be welded to a welding heat; pressing the said ends together; thoroughly working the peratures below 1075 G; and rapidly cooling to below 4:20" C.; substantially as described.

welded portions at temv 6. In the production of wrought manganese steel chain, the method of welding, working and heat-treating the links, which comprises bringing the ends to be welded to a welding heat; pressing the said ends together; thoroughly working the welded portions at temperatures below 1075 0.;

and rapidly cooling to below 420 0.; sub 'stantially as described.

7. In the production of wrought manga- 'nese steel'chain, the method of welding, working and heattreating the links, which comprises bringing the ends to be welded to a welding heat; pressing the said ends together; thoroughly working the welded portions at temperatures below 107 5 0.; equal izing the temperature in the welded and worked links between 800 0. and 107 5 0.; and rapidlycoolin to below 420 0.; substantially as descri ed.

8. In the production of wrought manganese steel chain, the method of welding, working, and heat-treating the links, which comprises bringing the ends to be welded to a welding heat by the passage of an electric current; pressing the said ends together-i,

thoroughly working the welded portions at temperatures below. 1075"- 0.; heating the Welded and worked links to about 1000 0.;

and rapidly cooling'to below 420 0.; subforming the links; bringing the ends to be welded to a welding heat; pressing the said ends together and thereby welding them; thoroughly working the welded portions at temperatures below 1075 0.; and finally cooling the metal rapidly from about 1000 0. to below i20 0.; substantially as de scribed.

In testimony whereof I aflix my signature,

in presence of .two witnesses.

WINFIELD S. POTTER. Witnesses;

M. A. BILL, JOHN 0. 'PENNIE.

Copies of this patent may be obtained for five'cents each, by addressing the Commissioner of Patents,

Washington, D. G. v