US3766770A - Method of manufacturing forged crossing - Google Patents
Method of manufacturing forged crossing Download PDFInfo
- Publication number
- US3766770A US3766770A US00120197A US3766770DA US3766770A US 3766770 A US3766770 A US 3766770A US 00120197 A US00120197 A US 00120197A US 3766770D A US3766770D A US 3766770DA US 3766770 A US3766770 A US 3766770A
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- Prior art keywords
- rails
- crossing
- forging
- portions
- grooves
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
- B21K7/00—Making railway appurtenances; Making vehicle parts
- B21K7/02—Making railway appurtenances; Making vehicle parts parts for permanent way
Definitions
- ABSTRACT for the manufacture of forged crossings, which comprises forming a semimanufactured crossing having wheel grooves and guard rails by stamp-forging, with some machining or without any machining, a deformed, rectangular steel plate or billet, and forging and forming joining portions for connecting with ordinary rails at the ends of each of the'rail' portions on both ends ofsuch semimanufactured crossing.
- A. Assembled crossing constituted by a assembling a number of machined rails by a mechanical means.
- the object of the present invention is to produce a fixed crossing of integral construction which can withstand the increase in speed of conventional lines and which will not produce damages.
- the present invention is characterized in that a fixed crossing is made by stamp-forging a trapezoidal steel plate or billet, with or without some minor machining into the desired fixed crossing.
- the steel plate or billet is fashioned in such a way that the individual ends of the fixed crossing for joining the crossing to ordinary rails are sized and shaped the the same as the ordinary rails.
- the individual rail ends of the inventive fixed crossing can be directly attached to adjoining ordinary rails, and consequently the inventive crossing, which is made from only a single piece of material, is far stronger than prior art multiple piece fixed crossings.
- cavities or blow-holes inherently present in cast crossings are not present in the inventive forged crossing. Consequently, the inventive crossing is significantly stronger than prior art crossings made in final form by casting processes.
- FIGS. 1 through 15 show the first example where a machining is included partly;
- FIG. 1 is a sketch of a thick steel plate for material,
- FIG. 2 is a sketch of the material after subjected to the first process
- FIG. 3 is a sketch after the second process
- FIG. 4 is a sketch after the third process
- FIG. 5 is an enlarged sketch of both end portions after the fourth process
- FIG. 6 is a plan view after the machining process of rail grooves
- F IG. 7 is a plan view of completed product
- FIGS. 8 through 10 are cross sections through lines VIII-VIII, IX-IX, X-X in FIG. 7, respectively,
- FIG. 11 is an end view of a part of the completed crossing
- FIG. 12 is a sketch of a part of the completed crossing
- examples of v the pres- FIGS. 13 through 15 are sketches of different embodimental examples after subjected to the first to the third processes.
- FIG. 16 is a sketch of a thick steel plate for material
- FIG. 17 is a partial sketch after the first process
- FIG. 18 is a sketch after the second process
- FIG. 19 is a cross-sectional view along the line XIX- XIX,
- FIG. 20 is a partial sketch after the third process
- FIGS. 21 and 22 are sketches after the fourth process and a cross-sectional view along a line XXII-XXII, respectively,
- FIG. 23 is a partial sketch after the fifth process
- FIGS. 24 and 25 are a sketch after the sixth process and a cross-sectional view along a line XXV-XXV, respectively,
- FIG. 26 is a plan view after the seventh process.
- FIG. 27 is a sketch of the completed product.
- FIG. 1 Preparing. a thick steel plate or billet 1 of deformed, rectangular shape (a rectangular shape, with widthsgradually decreasing from one side to the other side), having a required dimension and necessary section (2', 3).
- FIG. 4 Cutting both ends of the semi-manufactured product shown in FIG. 3 for required lengths, opening the ends and expanding them to required angle 4, 5 using wedges.
- FIG. 5a Heating from the inner end A to the farther inner portion B of the cut portion 4shown in FIG. 4, and forming two rail portions 6, 7 by hot stampforging.
- FIG. 5b l-Iot stamp-forging the cut portion 5 shown in FIGS. 4 as before, to form two rail portions 8, 9 and guard rail portions 12, 13 beyond wheel grooves 10, 11 outside the rail portions 8, 9. Cut and remove the tip ends of said guard rail portions at appropriate position 14.
- FIGS. 6 and 7 Machining the product along a chain lines 15 and 15' connecting the inside line of the rail 6 and outside line of the rail 9 to extend the wheel groove 11 so as to form a wheel groove 16, similarly machining along chain lines 17 and 17 connecting'the inside line of the rail 17 and outside line of rail -8 to extend the sections shown in FIGS. 8, 9 and 10 and a cross-section shown in FIG. 1 1 at bothextremities of the ends. Then,
- FIG. 17 Hot-stamp forging the central portion C of a deformed, rectangular, thick steel plate or billet 24 having a required dimension and strength as shown in FIG. 16 to form a rail ridge 25 and guard rail portions 28, 29 across wheel grooves 26, 27 on both sides of said rail ridge 25, and further bend-forging grooves 30, 30 outside said guard rail portions 28, 29.
- FIG. 18 Bending the outside grooves 30, 30 by hotforging (30) to form a hollow desk-shaped crosssection having guard rail portions 28, 29, wheel grooves 26, 27, and a rail ridge 25 on the upper surface (FIG. 19-(D)).
- FIG. 20 Hot stamp forging the narrow unworked portion E of the steel plate 24 to form integrally rails 31, 32 on the extensions of said guard rails 28, 29 and grooves 33, 33 on both side thereof by bend-forging.
- FIG. 21 Bending outside grooves 33, 33 by hotforging (33'), and at the same time stamping between both of the rails 31, 32 to form two rails 31, 32 having a central portion D.
- FIG. 23 Hot-stamp forging the wide, unworked portion F of the steel plate 24 to form integrally rails 34, 35 on the extension of said rail ridge 25, and to-form integrally guard rails. 38, 39 on the extensions of said guard rails 28, 29 across the outside wheel grooves 36, 37, and further grooves 40, 40 outside thereof by bend- FIG.:24: Bending outside grooves 40, 40 by hot forging (40') and simultaneously stamping between the rails 34, 35 to form a hollow, desk-shaped cross-section having hollow portions D at the base portion (FIG. 25-(D-)).
- FIG. 26 Cutting by hot forging between rails 31, 32
- FIG. 27 Overall stamp-forging the'whole body of crossing thus formed roughly, and laterally forging joining portions 43 at the end portions of rails which serve to connect with ordinary rails, and further machining decarbonized layers of rail surface 31, 35, 32 and 34, thus the crossing is completed.
- the crossing according to the present invention can roughly be formed by forging alone (partly including machining), it is possible to provide a crossing, which is such a large piece of construction, with the whole body as. an integral construction and also as a hollow body, so that it is uniform all over the material and which has an elasticity, and it is free of joining portion, and there is no weak portion against vibration or shock due to connecting points and mold cavities as in the conventional products.
- Method of manufacturing a forged crossing characterized by the steps of machining grooves in a deformed, trapezoidal, thick steel plate or billet longitudinally along both sides thereof, bending the grooves so as to form hollow portions and desk-shaped crosssection, cuttingand widening the end portions of said plate or billet toform incipient rails, stamp-forming said incipient rails to form rails, wheel grooves and guard rails, machining wheel grooves at the central portionso that rails at both ends intersect therein, and forging and forming connecting portions at each of the rails on both ends-of thecrossing to which ordinary 2.
- a process according to claim .1. wherein the rails formed at the ends of the forged crossing are congruent in cross-section to said ordinaryrailsn Y 3.
- a process according to claim 2 further comprising shaping the. endof each of said rails so that it is similar in'shape to the ends of said ordinary rails.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Forging (AREA)
Abstract
The present method is applied for the manufacture of forged crossings, which comprises forming a semi-manufactured crossing having wheel grooves and guard rails by stamp-forging, with some machining or without any machining, a deformed, rectangular steel plate or billet, and forging and forming joining portions for connecting with ordinary rails at the ends of each of the rail portions on both ends of such semi-manufactured crossing.
Description
United States Patent [1 1 Sato et al.
[ METHOD OF MANUFACTURING FORGED v CROSSING 75] Inventors: Yoshiaki Sato, Tokyo; Makoto Kagami, Yachiyo; Shigeroku Motaki, Tokyo; Masakazu Mitsukawa, Miki, all of Japan [73] Assignee: Japanese National Railway and Kabushiki Kaisha Mitsukawa Tekkosho, Miki-shi, Hyogo-ken, Japan [22] Filed: Mar. 2, 1971 [21] Appl. No.: 120,197
[30] Foreign Application Priority Data Apr. 2, 1970 Japan 45/2809] Apr. 2, 1970 Japan 45/28092 [5.2] US. Cl. 72/340, 246/468 [51] Int. Cl. B2ld 28/00, EOlb 7/10 [58] Field of Search 72/340; 29/34 R;
246/468 R, 469 R, 470 R, 471 R, 472 R [56] References Cited UNlTED STATES PATENTS 1,439,050 Alden 246/468 R 1 Oct. 23, 1973 1,442,919 l/l923 Alden 246/468 R Primary ExaminerCharles W. Lanham 4 E 2 m"r:R9 tM- Rogers Attorney Fleit, Gipple & Jacobson [57] ABSTRACT The present method is applied for the manufacture of forged crossings, which comprises forming a semimanufactured crossing having wheel grooves and guard rails by stamp-forging, with some machining or without any machining, a deformed, rectangular steel plate or billet, and forging and forming joining portions for connecting with ordinary rails at the ends of each of the'rail' portions on both ends ofsuch semimanufactured crossing.
3 Claims, 28 Drawing Figures PA IENTEB IN 2 3 ms SHEET 30F 7 IFIGQS F'IG.8
FIG.IO
F- l6. l2
'PAIEN IEU was ms I SHEET Q [If 7 mimosa 2a m SHEET 7 [IF 7 FIG.25
FIG.26
METHOD OF MANUFACTURING FORGED CROSSING This invention relates to a fixed crossing. Heretofore, following kinds of crossings are used:
A. Assembled crossing constituted by a assembling a number of machined rails by a mechanical means.
B. Cast crossing constituted by casting the whole integrally using high manganese steel as materials.
Turning now to the present state of affair in the train, the speed of a train increases rapidly following the trend of the times, and it becomes difficult to maintain a sufficient safety against vibrations due to speed-up or impact with the above-said crossings. Main causes thereof are: (A) with this assembled cross-ing, since it is constituted originally by assembling separated rails artificially, it is quite natural that there are weak points at the connecting points, and (B) with this cast system of high-manganese steel the presence of cavity or blowhole, which is the largest problem in the casting, is also an important cause of damage in a crossing, and the cast product of high-manganese steel is difficult to weld with ordinary rails.
The object of the present invention is to produce a fixed crossing of integral construction which can withstand the increase in speed of conventional lines and which will not produce damages. To this end, the present invention is characterized in that a fixed crossing is made by stamp-forging a trapezoidal steel plate or billet, with or without some minor machining into the desired fixed crossing. The steel plate or billet is fashioned in such a way that the individual ends of the fixed crossing for joining the crossing to ordinary rails are sized and shaped the the same as the ordinary rails. As a result, the individual rail ends of the inventive fixed crossing can be directly attached to adjoining ordinary rails, and consequently the inventive crossing, which is made from only a single piece of material, is far stronger than prior art multiple piece fixed crossings. Moreover, because of its method of manufacture, cavities or blow-holes inherently present in cast crossings are not present in the inventive forged crossing. Consequently, the inventive crossing is significantly stronger than prior art crossings made in final form by casting processes.
The invention will now be described referring to the drawings.
The appended drawings show ent invention, in which:
FIGS. 1 through 15 show the first example where a machining is included partly; FIG. 1 is a sketch of a thick steel plate for material,
FIG. 2 is a sketch of the material after subjected to the first process,
FIG. 3 is a sketch after the second process,
FIG. 4 is a sketch after the third process,
FIG. 5 is an enlarged sketch of both end portions after the fourth process,
.FIG. 6 is a plan view after the machining process of rail grooves,
F IG. 7 is a plan view of completed product,
FIGS. 8 through 10 are cross sections through lines VIII-VIII, IX-IX, X-X in FIG. 7, respectively,
FIG. 11 is an end view of a part of the completed crossing,
FIG. 12 is a sketch of a part of the completed crossing,
examples of v the pres- FIGS. 13 through 15 are sketches of different embodimental examples after subjected to the first to the third processes.
The second example (FIGS. 16 through 27) is one using partial forging, and in which FIG. 16 is a sketch of a thick steel plate for material,
FIG. 17 is a partial sketch after the first process,
FIG. 18 is a sketch after the second process,
FIG. 19 is a cross-sectional view along the line XIX- XIX,
FIG. 20 is a partial sketch after the third process,
FIGS. 21 and 22 are sketches after the fourth process and a cross-sectional view along a line XXII-XXII, respectively,
FIG. 23 is a partial sketch after the fifth process,
FIGS. 24 and 25 are a sketch after the sixth process and a cross-sectional view along a line XXV-XXV, respectively,
FIG. 26 is a plan view after the seventh process, and
FIG. 27 is a sketch of the completed product.
FIRST EXAMPLE (FIGS. 1 15) FIG. 1: Preparing. a thick steel plate or billet 1 of deformed, rectangular shape (a rectangular shape, with widthsgradually decreasing from one side to the other side), having a required dimension and necessary section (2', 3).
FIG. 4: Cutting both ends of the semi-manufactured product shown in FIG. 3 for required lengths, opening the ends and expanding them to required angle 4, 5 using wedges.
FIG. 5a: Heating from the inner end A to the farther inner portion B of the cut portion 4shown in FIG. 4, and forming two rail portions 6, 7 by hot stampforging.
FIG. 5b: l-Iot stamp-forging the cut portion 5 shown in FIGS. 4 as before, to form two rail portions 8, 9 and guard rail portions 12, 13 beyond wheel grooves 10, 11 outside the rail portions 8, 9. Cut and remove the tip ends of said guard rail portions at appropriate position 14.
FIGS. 6 and 7: Machining the product along a chain lines 15 and 15' connecting the inside line of the rail 6 and outside line of the rail 9 to extend the wheel groove 11 so as to form a wheel groove 16, similarly machining along chain lines 17 and 17 connecting'the inside line of the rail 17 and outside line of rail -8 to extend the sections shown in FIGS. 8, 9 and 10 and a cross-section shown in FIG. 1 1 at bothextremities of the ends. Then,
in order to form connecting portions 23 with ordinary rails 19, forging the rail portions 6, 7, 8, 9 and the adjacent portions shown in FIG. 5, and laterally stamping them in directions shown by arrows 20 to form them as shown in FIG. 11. In this case, no difficultyis found at the central joining portions 21. In order to obtain a product free of said joining portion 21, working is effected similar to that shown in FIGS. 13 through 15 without forming hollow portions 22 at the rail portions 6, 7, 8, 9, and as for the other portions, working similar to that shown in FIGS. 1 through 12 and finally forging the rail portions laterally. It is to be understood that this forging.
process is included also in the scope of the present invention.
SECOND EXAMPLE (FIGS. 16 27):
FIG. 17: Hot-stamp forging the central portion C of a deformed, rectangular, thick steel plate or billet 24 having a required dimension and strength as shown in FIG. 16 to form a rail ridge 25 and guard rail portions 28, 29 across wheel grooves 26, 27 on both sides of said rail ridge 25, and further bend-forging grooves 30, 30 outside said guard rail portions 28, 29.
FIG. 18: Bending the outside grooves 30, 30 by hotforging (30) to form a hollow desk-shaped crosssection having guard rail portions 28, 29, wheel grooves 26, 27, and a rail ridge 25 on the upper surface (FIG. 19-(D)).
FIG. 20: Hot stamp forging the narrow unworked portion E of the steel plate 24 to form integrally rails 31, 32 on the extensions of said guard rails 28, 29 and grooves 33, 33 on both side thereof by bend-forging.
FIG. 21: Bending outside grooves 33, 33 by hotforging (33'), and at the same time stamping between both of the rails 31, 32 to form two rails 31, 32 having a central portion D.
FIG. 23: Hot-stamp forging the wide, unworked portion F of the steel plate 24 to form integrally rails 34, 35 on the extension of said rail ridge 25, and to-form integrally guard rails. 38, 39 on the extensions of said guard rails 28, 29 across the outside wheel grooves 36, 37, and further grooves 40, 40 outside thereof by bend- FIG.:24: Bending outside grooves 40, 40 by hot forging (40') and simultaneously stamping between the rails 34, 35 to form a hollow, desk-shaped cross-section having hollow portions D at the base portion (FIG. 25-(D-)).
rails can be connected.
. FIG. 26: Cutting by hot forging between rails 31, 32
processes, and cutting the tip portions of the guard rails 38, 39 at appropriate lengths 42.
FIG. 27: Overall stamp-forging the'whole body of crossing thus formed roughly, and laterally forging joining portions 43 at the end portions of rails which serve to connect with ordinary rails, and further machining decarbonized layers of rail surface 31, 35, 32 and 34, thus the crossing is completed.
Since the crossing according to the present invention can roughly be formed by forging alone (partly including machining), it is possible to provide a crossing, which is such a large piece of construction, with the whole body as. an integral construction and also as a hollow body, so that it is uniform all over the material and which has an elasticity, and it is free of joining portion, and there is no weak portion against vibration or shock due to connecting points and mold cavities as in the conventional products.
We claim:
1. Method of manufacturing a forged crossing characterized by the steps of machining grooves in a deformed, trapezoidal, thick steel plate or billet longitudinally along both sides thereof, bending the grooves so as to form hollow portions and desk-shaped crosssection, cuttingand widening the end portions of said plate or billet toform incipient rails, stamp-forming said incipient rails to form rails, wheel grooves and guard rails, machining wheel grooves at the central portionso that rails at both ends intersect therein, and forging and forming connecting portions at each of the rails on both ends-of thecrossing to which ordinary 2. A process according to claim .1. wherein the rails formed at the ends of the forged crossing are congruent in cross-section to said ordinaryrailsn Y 3. A process according to claim 2 further comprising shaping the. endof each of said rails so that it is similar in'shape to the ends of said ordinary rails. 3
Claims (3)
1. Method of manufacturing a forged crossing characterized by the steps of machining grooves in a deformed, trapezoidal, thick steel plate or billet longitudinally along both sides thereof, bending the grooves so as to form hollow portions and desk-shaped cross-section, cutting and widening the end portions of said plate or billet to form incipient rails, stamp-forming said incipient rails to form rails, wheel grooves and guard rails, machining wheel grooves at the central portion so that rails at both ends intersect therein, and forging and forming connecting portions at each of the rails on both ends of the crossing to which ordinary rails can be connected.
2. A process according to claim 1 wherein the rails formed at the ends of the forged crossing are congruent in cross-section to said ordinary rails.
3. A process according to claim 2 further comprising shaping the end of each of said rails so that it is similar in shape to the ends of said ordinary rails.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2809170A JPS499956B1 (en) | 1970-04-02 | 1970-04-02 | |
JP2809270A JPS499957B1 (en) | 1970-04-02 | 1970-04-02 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3766770A true US3766770A (en) | 1973-10-23 |
Family
ID=26366128
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00120197A Expired - Lifetime US3766770A (en) | 1970-04-02 | 1971-03-02 | Method of manufacturing forged crossing |
Country Status (2)
Country | Link |
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US (1) | US3766770A (en) |
CA (1) | CA926106A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3543141A1 (en) * | 1984-12-12 | 1986-07-17 | Petroleum Recovery Consultants A/S, Stjördal | DEVICE FOR TESTING LIQUIDS |
FR2646115A1 (en) * | 1989-04-21 | 1990-10-26 | Kihn Sarl | METHOD FOR MANUFACTURING NEEDLES FOR THROAT RAILS AND ONE-PIECE NEEDLE CARRIED OUT BY THIS PROCESS |
US5618013A (en) * | 1995-08-10 | 1997-04-08 | Cogifer- Compagnie Generale D'installations Ferroviaires (Societe Anonyme A Directoire) | Movable point for a crossing frog for railway apparatus of very great length, incorporated in long welded rails |
CN104259797A (en) * | 2014-09-28 | 2015-01-07 | 偃师市华信机械有限公司 | Forging method of iron pedestal for high-speed rail |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1439050A (en) * | 1920-05-25 | 1922-12-19 | Alden Charles Ames | Process of making railroad frogs and product thereof |
US1442919A (en) * | 1920-05-25 | 1923-01-23 | Alden Charles Ames | Process of making railroad frogs and product thereof |
-
1971
- 1971-03-02 US US00120197A patent/US3766770A/en not_active Expired - Lifetime
- 1971-03-31 CA CA109293A patent/CA926106A/en not_active Expired
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1439050A (en) * | 1920-05-25 | 1922-12-19 | Alden Charles Ames | Process of making railroad frogs and product thereof |
US1442919A (en) * | 1920-05-25 | 1923-01-23 | Alden Charles Ames | Process of making railroad frogs and product thereof |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3543141A1 (en) * | 1984-12-12 | 1986-07-17 | Petroleum Recovery Consultants A/S, Stjördal | DEVICE FOR TESTING LIQUIDS |
FR2646115A1 (en) * | 1989-04-21 | 1990-10-26 | Kihn Sarl | METHOD FOR MANUFACTURING NEEDLES FOR THROAT RAILS AND ONE-PIECE NEEDLE CARRIED OUT BY THIS PROCESS |
BE1004242A3 (en) * | 1989-04-21 | 1992-10-20 | Kihn Sarl | Method for switching tracks for throat and referral a piece produced by the method. |
US5618013A (en) * | 1995-08-10 | 1997-04-08 | Cogifer- Compagnie Generale D'installations Ferroviaires (Societe Anonyme A Directoire) | Movable point for a crossing frog for railway apparatus of very great length, incorporated in long welded rails |
CN104259797A (en) * | 2014-09-28 | 2015-01-07 | 偃师市华信机械有限公司 | Forging method of iron pedestal for high-speed rail |
Also Published As
Publication number | Publication date |
---|---|
CA926106A (en) | 1973-05-15 |
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