US939164A - Method of producing finished shapes from manganese steel. - Google Patents

Description

- suited for the production of rails, fo'r'rail- 870 C. The temperature is then rapidly raised to from 995 C. to 1065 0., spec fic? heating the ingot, preferably in successive shape, with an intermediate re-heating, if

UNITED STATES PATENT OFFICE.

'WINFIELD S. POTTER, OF NEW YORK, N. Y., ASSIGNOR T0 MANGANESE STEEL BAIL COMPANY, OF MAHWAH, NEW J ERSEY, A CORPORATION OF NEW JERSEY.

' METHOD or PRODUCING FINISHED snares FROM MANGANESE STEEL.

Specification of Letters Patent.

Patented Nov. 2, 1909.

No Drawing. Original application filed may a, 1906, Seria1-No.'315,83,1. Rehewed January a1,19o7,seriai No. 355,136. Divided and this'application filed September 22, 1909. Serial No. 518,929

To all whom it may concern:

Be it known that I, VVINFIELD S. POTTER, a citizen of the'United States, residing at New York, in the county of New York and State of Yew York, have invented a certain new and useful Improvement in Methods of Producing Finished Shapes from Manganese Steel, of' which the following is a specification.

Manganese steel is material which may be given great toughness, hardness and resist: ance to abrasion by subjecting it to suitable heat treatment. It is therefore especially ways. Heretofore, however, it has been found impossible to roll manganese steel into rails or other shapes, on account of the. fact that the metal lacks cohesion when hot, so that the cast ingot is crushed into pieces instead of being elongated when subjected to the action of rolls. Such rails as are now in use are therefore produced by casting the metal in molds. a

The present invention relates to a method of producing finished shapes from main ganese steel, whereby an ingot may be made sufliciently coherent to elongate without crushing in the rolling or shaping thereof. The method, generally stated, consists in stages, up to a high temperature, cooling the heated ingot to a lower temperature, and rolling it, preferably in two stages, the ingot being first heated to a low temperature and subjected to the action of roughing and compressing rolls, and then heated to a high temperature and rolled to finished necessary. The rolled product is then quenched, from a suitable temperature, to give it the requisite toughness.

The preferred complete mode of procedure is as follows: An ingot is cast, large end downward, in a mold of the usual form, the molten steel being preferably introduced into the mold through a fire-brick runner to decrease piping. The ingot is then slowly and evenly heated, preferably stand-- ing on end, and in a reducing atmosphere, for example, to a temperature between 735 C. and 930 C.,""and specifically to about 'bolts'while hot; from the rolls; The rails are ally to about 1040 0., at approximatelywhich temperaturethe metal becomes tender]- and is liable to crack if further heated rapidly, and from this point, the metal is slowlyv heated to-t-he maximumftemperature. permissible, between 1065 C. and1l260'G., specifically to about; 1205" O. This high temperature gives a uniform molecular structure to the steel, removing segregation and apparently causing the particles of "steel toweld together or firmly cohere. The hotjingot is now subjected to an annealing treatment by being cooled. This cooling ispreferably effected in a non-oxidizing atmosphere, the temperature being, first slowly reduced to avoid rupture, and then quickly lowered until recrystallization is complete, which oc curs at between 650 C. and 705 C; This annealing step is of'especial importance, cooperating with the high temperature previously used to produce even crystallization,

high-cohesion and uniform structure. --The ,,75 annealed mgot is now re-heated to a lowi temperature, suflicientto enable it-to be 1 rough rolled and compressed, dependent on the size of the ingot and power of the rolls,- and ranging from 870 C, to 1065 'C.- or upward. The initial'rolling is preferably efi'ected by Gothic rolls, the reductionin the first few passes being very slight, for example, one-quarter. of an inch in the first two passes on each sideffor fa-twelve inch ingot. The bloomis n'ow re-heated'to the maximum temperature, that is, to "the temperature to which it was originally heated, say from 1065- C. to 1205 C; and rolled to finished shape. In re'-heating,;-the ingot should lie on its sideand should betu-rned through an angle of 180 severa ines to insure even heating." The rails should be sawed to length and punched; for fisl1plate now subjected, to a" quenching operation, either direct from the rolls ifsufliciently hot, or after re-heating. The rails should be arranged base downward' in the re-heating furnace. and shouldthence-be drawn into a suitable rack capable of beingsubmerged in water.

V The above described method is not claimed herein, as such forms the subject-matter of. a pending application filed by the applicant on the 8th day of May, 1906, and bearing omitted; for example, if the ingot is taken direct from the mold with its center say at being omitted as above described, the ing' ot .that'the cooling or annealing step may be be taken direct from themolds to a soaking i pit, wherein their temperature will become g equalized. The slow preliminary heating to a temperature between 735 C. and 930 C., 5 as heretofore mentioned, may then be a temperature of from 1300 C. to 1200 C.,.; and havin 'a skin temperature of say l000 E C. to 900 6.,it may be placed in the soaking pit wherein the temperatures will be equalized, for example, at 1205 C. preferably not 5 above. 1260 C., and as the mass is relatively coherent at this temperature, and has not L been permitted to crystallize, it is-obvious omitted.

In somev instances, and especially with small ingots, the initial rough rolling may be omitted, the ingots being rolled to a finish in one heat, the cooling or annealing step in such instance being taken direct from the mold to the soaking pit wherein its temperatures become equalized, and is then taken to the rolls. This necessitates exact heating, accurate rolls and slight reductions l in the first few )asses, for. example, one- E eighth inch in a our inch ingot at a temperature of 1095 C., using rolls with a Gothic pass. On the other hand, the reducl tion of large ingots to small shapes, especially to thin sheets, may necessitate intermediate re-heating of the bloom during the i shaping.

The cooling .of the ingot for annealing, l and that of the finished product for tough- 1 ening, may be effected by subjecting the metal to the action of steam. In general, however, it is preferred to anneal either in the heating furnace or in the air, and to quench in water. Small ingots may be annealed by. quenching in water.

- WVhile the reduction of the ingots by means of rolls only, has been described, it will be understood that a hammer or press may be employed, if preferred.

-l,,,The method of producing finished shapes from manganese steel, which consists in slowly heating the ingot hot from the heat of casting, from a temperature between 995* C. and 1065 C. to the maximum temperature, and until the temperatures of the ingot are equalized, then slightly reducing said ingot and then shaping it.

2. The method of producing finished shapes from manganese steel, which consists in slowly heating an ingot while still hot from the heat of casting, from a. temperature approximating 1040 C. to approximately 1205 0., maintaining the heat until the temperatures of said ingot are equalized. and then shaping.

3. The method of producing finished shapes from manganese steel, which consists in' slowly heating an ingot while still hot from the heat of casting, from a temperature approximating 1040 C. to approximately 1205 (3., maintaining the heat until the temperatures of said ingot are equalized, then subjecting the ingot to slight reductions, and then shaping it.

I. The method of producing finished shapes from manganese steel, whlch consists 111 arresting the cooling of the ingot while still hot ,from the heat of casting, at a temperature above 735 (1, then immediately reheating, and subsequently shaping it.

5. The method of producing 'lllllfiliml shapes from manganese steel, which consists in arresting the cooling of an.ingot or body 5 of metal, from the heat of casting by heating the same to a temperature not above 1260"" (L, and subsequently shaping the same, the metal being slowly heated at temperatures above 1040 C.

6. The method of producingfinished shapes fronrimanganese steel, which consists in arresting the cooling from the heat of casting by heatlng the same in a furnace toa temperature not above 1260 (1., lightly working the same, and then shaping it.

7. The method of producing finished shapes from manganese steel, which consists in arresting the cooling of the metal, hot from the heat of casting, at a temperature above a red heat, heating said body slowly at temperatures above l04c0 (l, arresting the heating at a predetermined temperature not above 1260 C. and subsequently shaping the bodyof metal. I

In testimony whereof, I afiix my signature, in the presence of two witnesses.

' VVINFIELD S. POTTER Witnesses PARKER COOK,

M. VAN NORTWICK.