Claims
- 1. A method of manufacturing a railroad frog crossing bolt and nut assembly for clamping railroad sections together, said method comprising:
- a) selecting an unthreaded bolt having an elongated cylindrical shank body of at least 8.0 inches, said shank body having a first body portion with a given diameter of at least about 1.0 inch and a second body portion with a given diameter of less than the given diameter of said first body portion, and an integral square head having an orthogonal bearing surface and positioned adjacent to said first body portion;
- b) forming threads on said second body portion by a rolling action to provide increased physical strength to the threads to about the diameter of said first body portion;
- c) machining said orthoganal bearing surface to a preselected mechanical tolerance with said surface and said first body portion being mutually perpendicular;
- d) selecting a lock nut adapted to be threaded onto said threads on said second body portion after said shank body has been passed through at least two of said rail sections;
- e) forming internal, continuous threads in said nut to adapt said nut to be screwed onto said second body portion; and
- f) forming at least one mechanically deformed indentation on said nut and intersecting said threads whereby said threads are deformed to provide an interference fit when said nut is screwed onto said second body portion.
- 2. The method as defined in claim 1, including the step of heat treating said nut prior to forming said at least one mechanically deformed indentation.
- 3. The method as defined in claim 2, including the step of forming a protruding mechanical annular bearing surface on an end of said nut which is opposite said machined indentation for improved bearing against a flange of said rail section.
- 4. The method as defined in claim 2, wherein said nut has two mechanical indentations formed in a rear end of said nut and said indentations are diametrically spaced from another.
- 5. The method as defined in claim 2, wherein said nut has four mechanical indentations formed in a rear end of said nut and said indentations are equally spaced from another.
- 6. The method as defined in claim 2, wherein said at least one mechanical indentation extends about 0.1 inch into said nut.
- 7. The method as defined in claim 2, wherein said at least one mechanical indentation extends into said nut a distance sufficient to distort two threads of said nut.
- 8. The method as defined in claim 1, including the step of forming a tapering frusco-conical forward end on said second body portion prior to forming threads on said second body portion and not threading at least part of the frusco-conical forward end when forming threads on said second body portion, said frusco-conical forward tapering inwardly at an angle of at least about 14.degree. relative to a longitudinal centerline of said bolt for a distance of about one-half inch whereby the unthreaded part of said frusto-conical forward end permits alignment of said rail sections to minimize distorting threads on said second body portion.
- 9. The method as defined in claim 8, wherein said angle is about 14.degree. to about 16.degree..
- 10. The method as defined in claim 1, including the step of applying a corrosion resistant plating to said bolt and said nut and subsequently applying a baked-on finish to protect said bolt and said nut from hydrogen embrittlement.
- 11. The method as defined in claim 1, including the step of heat treating said bolt whereby the core of said bolt has a rockwell core hardness of at least about 33 and a rockwell surface hardness of up to about 58.6.
- 12. The method as defined in claim 11, wherein said bolt is formed from carbon steel, said carbon steel having a tensile strength of at least about 150,000 psi, a rockwell core hardness of about 33 HRC to about 39 HRC and a rockwell surface hardness of up to about 58.6 HRC.
- 13. The method as defined in claim 1, wherein said diameter of said second body portion has a tolerance of not more than about 0.012 inch.
- 14. The method as defined in claim 1, including the step of applying a wax coating to said nut to reduce friction when said nut is screwed into said bolt.
- 15. The method as defined in claim 1, wherein said first body portion is unthreaded.
- 16. The method as defined in claim 1, wherein the second body portion of said shank body having a given diameter of about 1.0 inch to about 1.375 inch and maintained within a tolerance of about 0.012 inch.
- 17. The method as defined in claim 1, wherein the length of said shank body is about 8 inches to about 30 inches.
- 18. The method as defined in claim 1, wherein the length of the threaded second body is up to about 4.25 inches.
- 19. The method as defined in claim 1, wherein said lock nut is formed from carbon steel, said carbon steel having a rockwell hardness of about 26 HRC to about 32 HRC and a proof load of up to about 150,000 psi.
- 20. A method of manufacturing a railroad frog crossing bolt for clamping railroad sections together, said method comprising:
- a) selecting an unthreaded bolt having an elongated cylindrical shank body, said shank body having a first body portion with a given diameter and a second body portion with a given diameter of less than the given diameter of said first body portion, and an integral head having an orthogonal bearing surface and positioned adjacent to said first body portion;
- b) forming threads on said second body portion by a rolling action to provide increased physical strength to the threads to about said given diameter of said first body portion;
- c) machining said orthoganal bearing surface to a preselected mechanical tolerance with said surface and said first body portion being mutually perpendicular; and
- d) forming a tapering frusco-conical forward end on said second body portion prior to forming threads on said second body portion and not threading at least part of the frusco-conical forward end when forming threads on said second body portion, said frusco-conical forward tapering inwardly at an angle of at least about 14.degree. relative to a longitudinal centerline of said bolt for a distance of at least about one-half inch whereby the unthreaded part of said frusto-conical forward end permits alignment of said rail sections to minimize distorting threads on said second body portion.
- 21. The method as defined in claim 20, including the step of applying a corrosion resistant plating to said bolt and subsequently applying a baked-on finish to protect said bolt from hydrogen embrittlement.
- 22. The method as defined in claim 20, including the step of heat treating said bolt whereby the core of said bolt has a rockwell core hardness of at least 33.
- 23. The method as defined in claim 20, including the step of heat treating said bolt whereby the surface of said bolt has a rockwell surface hardness of at least about 58.6.
- 24. The method as defined in claim 20, wherein said diameter of said second body portion has a tolerance of up to about 0.012 inch.
- 25. The method as defined in claim 20, wherein said given body diameter of said first body portion is at least about one inch.
- 26. The method as defined in claim 20, wherein said shank body is at least about eight inches.
- 27. The method as defined in claim 20, wherein said head is square shaped.
- 28. The method as defined in claim 20, wherein said bolt is made of carbon steel.
- 29. The method as defined in claim 20, wherein said angle is about 14.degree. to about 16.degree..
- 30. The method as defined in claim 20, wherein the second body portion of said shank body having a given diameter of about 1.0 inch to about 1.375 inch and maintained within a tolerance of about 0.012 inch.
- 31. The method as defined in claim 20, wherein the length of said shank body is about 8 inches to about 30 inches.
- 32. The method as defined in claim 20, wherein said bolt is formed from carbon steel, said carbon steel having a tensile strength of at least about 150,000 psi, a rockwell core hardness of about 33 HRC to about 39 HRC and a rockwell surface hardness of up to about 58.6 HRC.
- 33. The method as defined in claim 20, wherein the length of the threaded second body is up to about 4.25 inches.
- 34. The method as defined in claim 20, including the steps of:
- (e) selecting a lock nut adapted to be threaded onto said threads on said second body portion after said shank body has been passed through at least two of said rail sections;
- (f) forming internal, continuous threads in said nut to adapt said nut to be screwed onto said second body portion; and
- (g) forming at least one mechanically deformed indentation on said nut and intersecting said threads whereby said threads are deformed to provide an interference fit when said nut is screwed onto said second body portion.
- 35. The method as defined in claim 34, including the step of heat treating said nut prior to forming said at least one mechanically deformed indentation.
- 36. The method as defined in claim 34, including the step of applying a corrosion-resistant plating to said nut and subsequently applying a baked-on finish to protect said nut from hydrogen embrittlement.
- 37. The method as defined in claim 34, including the step of forming a protruding mechanical annular bearing surface on an end of said nut which is opposite said machined indentation for improved bearing against a flange of said rail section.
- 38. The method as defined in claim 34, wherein said nut has two mechanical indentations formed in a rear end of said nut and said indentations are diametrically spaced from another.
- 39. The method as defined in claim 38, wherein said nut has four mechanical indentations formed in a rear end of said nut and said indentations are equally spaced from another.
- 40. The method as defined in claim 38, wherein said at least one mechanical indentation extends about 0.1 inch into said nut.
- 41. The method as defined in claim 34, including the step of applying a wax coating to said nut to reduce friction when said nut is screwed into said bolt.
- 42. The method as defined in claim 34, wherein said lock nut is formed from carbon steel, said carbon steel having a rockwell hardness of about 26 HRC to about 32 HRC and a proof load of up to about 150,000 psi.
Parent Case Info
This is a division of application Ser. No. 08/124,708 filed Sep. 21,1993, now U.S. Pat. No. 5,413,442.
US Referenced Citations (12)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1273146 |
May 1972 |
GBX |
Non-Patent Literature Citations (1)
Entry |
"Maintenance of way fasteners Solutions", pp. III-5 to III-6, III-9, VI-7 to VI-10, Camcor Textron. |
Divisions (1)
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Number |
Date |
Country |
Parent |
124708 |
Sep 1993 |
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