AU599274B2

AU599274B2 - Rail joint

Info

Publication number: AU599274B2
Application number: AU25780/88A
Authority: AU
Inventors: Hans Guntermann
Original assignee: Elektro Thermit GmbH
Current assignee: Goldschmidt ETB GmbH
Priority date: 1987-11-20
Filing date: 1988-11-21
Publication date: 1990-07-12
Anticipated expiration: 2008-11-21
Also published as: AU2578088A

Description

laii 599 274 S F Ref: 43219 FORM COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

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Accepted: Published: Priority: Related Art: I t t I Name and Address of Applicant: Elektro-Thermit GmbH Gerlingstrasse 4300 Essen 1 FEDERAL REPUBLIC OF GERMANY NOT KNONN Actual Inventor: p a P P Address for Service: Spruson Ferguson, Patent Attorneys, Level 33 St Martins Tower, 31 Market Street, Sydney, New South Wales, 2000, Australia Complete Specification for the invention entitled: Rail Joint The following statement is a full description of this invention, including the best method of performing it known to me/us REPRINT OF RECEIPT SOO3757 21/1/~8 5815/4

L

i 1 The present invention relates to joining rails upon which railway vehicles pass.

To eliminate the noise and vibration caused by rail joins, rails now are frequently welded at their adjacent ends. Previous methods of joining pairs of rails has included providing a gap between the ends (approximately mm) and then locating adjacent the ends a mould into which aluminothermically produced steel is poured to join the ends. Usually, the ends are preheated.

The aluminothermic moulded mass is composed so that the resulting steel join has the same strength and wear characteristics as the pair of rails joined thereby.

Generally, excess material is removed by grinding and more particularly coarse grinding while the metal is still hot. Once the metal has cooled, the grinding is finished to provide a suitable profile.

a 15 Attempts have been made to electrically or gas weld abutting ends of So rails. This process usually demands a higher degree of craftsmanship and 0 9 accordingly has disadvantages when generally used.

oW Due to the thermal expansion of rails, the joins are subjected to considerable stress. This stress problem is exacerbated by side and O 20 vertical loading applied thereto by the wheels of railway vehicles passing therealong. Due to the high stresses involved, previously known methods of joining rails have suffered from the disadvantage that notches and irregularities in the mould have acted as stress raisers and have resulted Q 'in fractures.

004000 It is the object of the present invention to overcome or I 044 substantially ameliorate the above disadvantages.

SThere is disclosed herein a rail joint connecting a pair of rail ends/, with each rail having a foot and a rail head from which there depends a rail web, said joint including a pre-fabricated reinforcing member conforming to and placed adjacent the webs so as to generally bridge the rail ends, and a weld joining the reinforcing member to each end portion.

Preferably, a gap exists between the rail ends into which aluminothermically produced steel is poured to join the ends.

fhere is further disclosed herein a method of producing a rail joint comprising the steps of: :providing a pair of rail end portions, with each end portion having a rail head, web and foot; v locating the rail end portions so as to be generally coaxial and o spaced so as to provide a gap of desired width; DG:0888t -r"l -r;rr T -2locating about the rail end portions a mould which co-operates with the rail end portions to provide a mould cavity; locating a reinforcing member adjacent both webs of both rail end portions limiting the gap; and pouring into said cavity nolten metal to join the rail end portions and reinforcing member.

A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings, wherein: Fig. 1 is a schematic perspective view of a pair of rail ends connected by a rail joint; ,oO Fig. 2 is a schematic perspective view of a mould half employed to form the joint of Figure 1; e Fig. 3 is a schematic perspective view of a further rail joint to that shown in Figure 1; and Fig. 4 is a schematic perspective view of a still further rail joint.

:In Figures 1 and 2 of the accompanying drawings there is schematically depicted a pair of rail ends 1 and 2 connected by a rail joint 16. Each of the rail end portions 1 and 2 has a rail head 17 and a rail foot 18 connected by a vertical web 19.

o 20 The rail joint 16 has a head portion 3 and a foot portion 4 as well as a web portion 20. However, the joint 16 also includes a pre-fabricated reinforcing member 6.

In forming the joint 16, the rail end portions 1 and 2 are located so as to provide a desired gap. The reinforcing member would have a thickness approximating the gap between the rail end portions 1 and 2.

In forming the joint 16, a pair of mould halves 7 are provided which engage the end portions 1 and 2 so as to provide a sealed mould cavity.

The mould cavity would include a recess within which the reinforcing member 6 is located. Preferably the reinforcing member 6 would have a contour which fitted the contour of the web 19. The mould 7 would also have cavities 8 and 21 which would form enlarged areas surrounding the reinforcing member 6.

When the mould cavity is formed, aluminothermically produced steel is delivered into the mould to form the remainder of the joint 16 apart from the reinforcing member 6. Thereafter, the joint 16 is ground so that the head 3 conforms to the head portions 17 of the rail end portions 1 and 2.

The reinforcing member 6 is pre-fabricated and is free of notches, Perforations and other stress raisers.

In Figure 3, the rail end portions 1 and 2 are joined by a STg f..323r 1 -r ii-; 1_ i i i-i 3reinforcing member 11 spaced from the webs 19 but joined to the rail heads 17 and rail feet 18. The reinforcing member 11 would be joined to the rail end portions 1 and 2 by ieans of welds 12 and 13. The rail head portion 17 would also be joined by means of a weld 19, together with the rail feet 18. Again, the reinforcing member 11 would be formed so as to be free of stress raisers as discussed above.

In Figure 4, the rail joint includes a reinforcing member 15 which conforms to the profile of the webs 19 and is joined thereto by means of a weld 10. Additionally the rail end portions 1 and 2 would be joined by a weld 14. Again, the reinforcing member 15 would be formed so as not to be provided with stress raisers such as notches and perforations.

In Figures 3 and 4, the rail end portions 1 and 2 may be joined by electric welding or gas welding processes.

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Claims

2. The rail joint of claim 1 wherein said reinforcing member extends generally longitudinally of the rail ends.
3. The rail joint of claim 2 wherein said reinforcing member has a configuration conforming to the webs and is in abutting relationship with respect thereto, and welded to the webs. 0 o ao 00 0 0, 0 .3 C 0
4. The rail joint of claim 2 wherein said reinforcing member is spaced from the webs and is welded to the rail heads and feet.
5. The rail joint wherein said reinforcing member extends generally normal to the webs.
6. The rail joint of claim 5 wherein said joint is formed by pouring between the rail ends aluminothermically produced steel.
7. A method of producing a rail joint comprising the steps of: providing a pair of rail end portions, with each end portion having a rail head, web and foot; locating the rail end portions so as to be generally coaxial and '3 I '3 spaced so as to provide a gap of desired width; locating about the rail end portions a mould which co-operates with the rail end portions to provide a mould cavity; 0 25 locating a reinforcing member adjacent both webs of both rail end r portions limiting the gap; and pouring into said cavity molten metal to join the rail end portions and reinforcing member.
8. The method of claim 7 further including grinding said joint so that a continuous surface is provided between the rail heads.
9. A rail joint substantially as hereinbefore described with reference to the accompanying drawings. A method of forming a rail joint, substantially as hereinbefore described with reference to the accompanying drawings. DATED this SECOND day of APRIL 1990 Elektro-Thermit GmbH Ni 6;,~t gi-/323r Patent Attorneys for the Applicant SPRUSON FERGUSON