GB2356658A

GB2356658A - Rail clip

Info

Publication number: GB2356658A
Application number: GB9927971A
Authority: GB
Inventors: Warwick Scott Faville; Peter Goodhind
Original assignee: Gantry Railing Ltd
Current assignee: Gantry Railing Ltd
Priority date: 1999-11-27
Filing date: 1999-11-27
Publication date: 2001-05-30
Also published as: GB9927971D0

Description

2356658 IMPROVEMENTS IN OR RELATING TO RAIL CLIPS This invention concerns

improvements in or relating to rail clips for railway or crane rails.

It is well known to fasten railway or crane rails to structures on which they are supported by clips arranged on both sides of the rail and spaced apart along the length of the rail. Many diverse designs of clips have been proposed for this purpose.

Typically, vehicles that travel on rails apply a vertical downward force and smaller horizontal side force to the rail. The rail commonly comprises a base seated on the support structure and a head connected to the base by a web. The head is spaced above the base and is engaged by a flanged wheel of the vehicle whereby the wheels are raised clear of the support structure.

Conventionally, the design of the rail is such that the base is wider than the head to provide stability from toppling over due to the side force.

Commonly, with railway rails, the base width and height might be of similar dimensions with the width of the top of the head being about half the width of the base. In this way, when the vertical force acting on the rail head is resolved with the horizontal force at the rail head, the line of action passes through the rail base. This ensures the rail will not topple over.

In some cases, the horizontal force to which the rail is subjected may be very high in relation to the vertical force. In such cases, when the horizontal and vertical forces are resolved, the line of action does not pass through the base and the rail is liable to topple over. One case where this 2 may occur is during an earthquake where the ground accelerates downwards at the same time as it accelerates horizontally which can result in any instantaneous toppling action if the rail is not fastened appropriately. Other cases where this occurs are during a tornado or hurricane resulting in conditions beyond normal design but which must be catered for. These conditions are more normally of concern when designing for the installation of cranes in sensitive facilities such as nuclear power stations or strategic ports and proposals include providing some suitable mechanism which fastens the crane down, for example a grip around the head of the rail.

The present invention has been made from a consideration of the problems created by extreme conditions for the stability of rails and in particular rails for cranes.

According to the present invention there is provided a rail clip for restricting movement of a rail relative to a support surface on which the rail is seated, the clip being adapted for mounting to one side of the rail and having a locating portion arranged to extend over a base of the rail towards a web of the rail connecting the base to a head of the rail, the locating portion being provided with a first stop providing an abutment for the web of the rail to limit horizontal movement of the rail, and a second stop providing an abutment for the base of the rail on one side of the web to limit vertical or rotational movement of the rail.

Both stops may be spaced from the adjacent surface of the rail in the installed position of the clip, whereby the clip is effective to restrict movement of the rail when subjected to loads above a pre-determined value. Thus, the clip may be employed for use in emergencies when the rail is subjected to high loads in extreme conditions such as an earthquake 3 with the rail being secured by other means where required for normal day to-day use. Such other means may be of simple, low cost construction for withstanding the loads occurring in normal day-to-day use with the invented clips provided for withstanding the higher loads in an emergency.

Alternatively, at least one of the stops may be arranged to contact the adjacent surface of the rail in normal use so as to provide location for the rail without additional fastening means.

Preferably, the clip comprises a base or mounting plate for securing the clip adjacent to the rail, and a head or locating plate connected thereto and extending over the base of the rail with the first and second stops provided by the locating plate.

Advantageously, the first stop is provided by an inner side edge of the locating plate with said inner side edge extending parallel to the web in the direction of the length of the rail. This arrangement provides a substantial abutment for contact with the web of the rail to resist horizontal or sideways movement of the rail.

Preferably, the second stop is provided by a lower surface of a flange or similar formation on the underside of the locating plate with said flange extending parallel to the base in the direction of the length of the rail.

This arrangement also provides a substantial abutment for contact with the base of the rail to resist vertical or rotational movement of the rail.

Preferably the second stop is arranged to overlie and contact the base of the rail at or near to the outer side edge of the base. This is where 4 rotational movement of the rail will initiate lifting movement of the rail and ensures the clip is effective to restrict such movement.

The first stop is arranged to contact the web between the base and head of the rail and may be arranged at any position therebetween. Preferably, the first stop is arranged at or above the mid-point of the web and more preferably under the head so as to resist sideways movement from forces applied to the head of the rail.

The clip may be made of metal such as steel which may be painted or treated to resist corrosion.

The locating plate may be releasably secured to the mounting plate with one or more bolts. The fastening between the plates may allow adjustment of the position of the locating plate to change the position of the stops relative to the rail.

The locating plate and mounting plate may have co-operating formations for transmitting loads applied to the locating plate from the rail to the mounting plate. For example, the flange providing the second stop may abut the inner side edge of the mounting plate.

The mounting plate may be secured by welding or by any other suitable means. Where welding is employed this may be at the inner side edge to resist rotation of the mounting plate about the outer side edge under the loads acting in use. This may be sufficient to secure the clip without requiring additional welding at the ends or outer side edge of the mounting plate.

The invention will now be described in more detail by way of example only with reference to the accompanying drawings wherein:- Figure 1 shows an end elevation, partly in section, of a rail and two clips 5 embodying the invention; Figure 2 shows a plan view of one of the clips shown in Figure 1; Figure 3 shows an end elevation, partly in section, similar to Figure I of a rail and two different clips embodying the invention; Figure 4 shows a plan view of the clip to the left of the rail in Figure 3; and Figure 5 shows a plan view of the clip to the right of the rail in Figure 3.

Referring first to Figures 1 and 2 of the drawings, there is depicted a rail 1 for a wheel 2 of a crane or similar vehicle (not shown).

The rail 1 has a head 3 connected to a base 4 by a web 5. The base 4 extends to either side of the head 3 and is approximately twice as wide as the head 3. The head 3 has a flat top wall 3a and parallel side walls 3b normal to the 25 top wall 3a. The crane wheel 2 has a peripheral groove 6 of channelsection for locating the wheel 2 on the head 3 of the rail 1. The base 4 of the rail 1 is flat on the underside 4a and seats on a support structure 7 such as a steel girder. The upper surface 4b of the base 4 is 30 inclined upwardly from the outer side edges 4c. to the web 5.

6 The web 5 is located centrally between the side edges 4c of the base 4 and has opposed parallel side walls 5a that extend vertically to the head 3. The underside 3c of the head is inclined downwardly from the side walls 5 3b to the web 5.

Mounted on the support structure 7 on opposite sides of the rail 1 are a pair of clips 8. Additional pairs of clips (not shown) are provided at intervals spaced apart along the length of the rail 1. In this embodiment the clips 8 are provided for restricting movement of the rail 1 under extreme conditions such as may occur during an earthquake where normal rail fasteners may not be able to withstand the large forces applied to the rail.

Each clip 8 is similar and comprises a lower mounting plate 9 and an upper restraining or locating plate 10. Both plates 9, 1.0 are made of steel but other metals or alloys may be used.

The mounting plate 9 is of rectangular shape and extends parallel to and is spaced from the adjacent edge 4c of the base 4 of the rail 1. The mounting plate 9 is secured to the support structure 7 by a fillet weld 11 at the inner side edge 9a.

The mounting plate 9 is higher than the base 2 and the upper locating plate 10 is also of rectangular shape but wider than the mounting plate 9 so as to extend over the tipper surface 4b of the base 4 towards the web 5.

The locating plate 10 is secured to the mounting plate 9 by a pair of bolts 12. Each bolt 12 has a hexagonal head 12a for engagement by a spanner or the like tool and a threaded shank 12b that extends through a hole 10a 7 in the locating plate 10 and engages a tapped hole 9b in the mounting plate 9.

The mounting plate 9 is positioned so that when the locating plate is attached a small clearance gap 13 is provided between the side walls 5a of the web 5 and the inner side edge 10b of the locating plates 10. The inner side edge 10b forms a stop to restrict sideways or horizontal movement of the rail 1 as described later.

The locating plate 10 is provided on the underside with a flange 14 extending towards the upper surface 4b of the base 4. The flange 14 is spaced from and parallel to the inner side edge 9a of the mounting plate 9 and is secured to the locating flange 10 by fillet welds 15 on each side. The flange 14 overlies the upper surface 4b of the base of the rail 1 and the lower surface 14a is inclined to be parallel to the upper surface 4b of the base.

When the locating plate 10 is attached to the mounting plate 9, a small clearance gap 16 is provided between the lower surface 14a of the flange and the upper surface 4b of the base 4 of the rail 1. The lower surface 14a forms a stop to restrict upwards or vertical movement of the rail 1 and/or rotational movement of the rail as described later.

In use, the rail 1 may be held in position by separate fastening means (not shown) capable of withstanding the forces arising under normal conditions and the clips 8 provide emergency or back-up fastenings to restrict movement of the rail 1 due to large forces arising in extreme conditions.

Thus, during an earthquake, the vertical force X from the crane wheel 2 30 may be zero and the horizontal force Y may be significant. As a result, 8 the rail 1 is displaced sideways until the web 5 engages the stop formed by the inner edge 10b of the locating plate 10 to the left of the rail. The rail 1 may also tend to rotate anti-clockwise due to the couple generated by the applied force from the wheel 2 and the resisting force at the stop 10b. Such rotation is restricted by engagement of the upper surface 4b of the base of the rail with the stop formed by the lower surface 14a of the flange 14 on the locating plate 10 to the right of the rail. In other words the rail 1 is positively located to restrain further movement on both sides by the clips 8.

As will be appreciated, the arrangement of the stops on each clip 8 provides a robust construction capable of withstanding high loads under extreme conditions which ensures the rail position is maintained and stability of the crane is unaffected.

Referring now to Figures 3 to 5 of the drawings, two modifications of the clip 8 are shown in which like reference numerals are used to indicate corresponding parts.

Figure 4 and the left hand side of Figure 3 depicts a clip 8 in which the mounting plate 9 and locating plate 10 can be secured together with a single bolt 12. For this, the flange 14 forming the stop on the underside of the locating plate 10 is formed so that the outer side edge 14b engages the inner side edge 9a of the mounting plate 9 both to transfer force from the rail 1 through the locating plate 10 to the mounting plate 9 and to prevent rotation of the locating plate 10 relative to the mounting plate 9.

A further feature of this design is the provision of a step 17 in the locating plate 10 which raises the stop formed by the inner side edge 10b so as to resist forces from the rail 1 at a higher position that the clip 8 9 shown in Figures 1 and 2 in which the locating plate 10 is flat. In addition, the flange 14 is formed integrally with the locating plate 10 which may be formed, for example, by extrusion and cut to the appropriate length as desired. Other arrangements for altering the height of the stop may be employed, for example one or more spacers between the plates 9, 10.

Figure 5 and the right hand side of Figure 3 depicts a clip 8 in which the locating plate 10 can be adjusted relative to the mounting plate 9 to adjust the size of the clearance gap 13 between the web 5 and the inner side edge 10b of the locating plate 10. For this, the locating plate 10 has a hole 18 for the bolt 12 which is oversize relative to the shank 12b of the bolt 12 and receives a cylindrical portion of an eccentric member 19 having an offset hole 20 for the bolt 12 such that rotation of the eccentric member 19 adjusts the lateral position of the locating plate 10 relative to the mounting plate 9. Other arrangements for adjusting the relative position of the plates may be employed, for example a slideway with adjusting screw for displacing the locating plate 10.

Although the invention has been described for application of the clips 8 as emergency clips operable to restrain movement of the rail 1 under extreme conditions with other clips provided where appropriate to carry the normal day to day loads, it will be appreciated the invention is not limited to such application.

Thus, the invented clips 8 may be arranged so that the inner side edges 10b of the locating plates 10 about the side walls 5a of the web 5 to locate the rail horizontally.

Alternatively, or additionally, the clips may be arranged so that the lower surfaces 14a of the flanges 14 about the upper surface 4b of the base of the rail to locate the rail 1 vertically. The inclination of the surfaces 14a, 4b may also provide horizontal location of the rail.

As will be appreciated the present invention provides a rail clip of simple construction which is easy to install and which can be used in addition to or in place of existing clips to provide location for a rail under extreme conditions.

While the invention has been described for a rail clip to secure a crane rail it will be understood that the rail clip may be used for rails for other types of heavy equipment or rail vehicles.

Claims

I I CLAIMS

1 A rail clip for restricting movement of a rail relative to a support surface on which the rail is seated, the clip being adapted for mounting to one side of the rail and having a locating portion arranged to extend over a base of the rail towards a web of the rail connecting the base to a head of the rail, the locating portion being provided with a first stop providing an abutment for the web of the rail to limit horizontal movement of the rail, and a second stop providing an abutment for the base of the rail on 10 one side of the web to limit vertical or rotational movement of the rail.

2. A rail clip according to claim 1 wherein, the first and second stops are spaced from the adjacent surface of the rail in the installed position of the clip for restricting movement of the rail when subjected to loads above 15 a pre-determined value.

3. A rail clip according to claim 1 wherein, at least one of the first and second stops is arranged to contact the adjacent surface of the rail in the installed position of the clip.

4. A rail clip according to any one of the preceding claims wherein, the clip comprises a base or mounting plate for securing the clip adjacent to the rail, and a head or locating plate connected thereto and extending over the base of the rail with the first and second stops provided by the 25 locating plate.

5. A rail clip according to claim 4 wherein, the first stop is provided by an inner side edge of the locating plate with said inner side edge extending parallel to the web in the direction of the length of the rail.

12

6. A rail clip according to claim 4 or clairn 5 wherein, the second stop is provided by a lower surface of a flange or similar formation on the underside of the locating plate with said flange extending parallel to the base in the direction of the length of the rail.

7. A rail clip according to any one of claims 4 to 6 wherein, the locating plate is releasably secured to the mounting plate.

8. A rail clip according to claim 7 wherein the locating plate is 10 secured to the mounting plate with one or more bolts.

9. A rail clip according to claim 7 or clairn 8 wherein the position of the locating plate is adjustable to change the position of the stops relative to the rail.

10. A rail clip according to any one of claims 4 to 9 wherein, the locating plate and mounting plate have co-operating formations for transmitting loads applied to the locating plate from the rail to the mounting plate.

11. A rail clip according to claim 10 wherein, the locating plate abuts the inner side edge of the mounting plate.

12. A rail clip according to any one of claims 4 to 11 wherein, in use, 25 the mounting plate is secured by welding.

13. A rail clip according to claim 12 wherein, the mounting plate is welded at the inner side edge.

13

14. A rail clip according to any one of the preceding claims wherein, the second stop is arranged to overlie the base of the rail at or near to the outer side edge of the base.

15. A rail clip according to any one of the preceding claims wherein, the first stop is arranged on one side of the web between the base and head of the rail.

16. A rail clip according to claim 15 wherein, the first stop is arranged 10 at or above the mid-point of the web.

17. A rail clip according to claim 16 wherein, the first stop is arranged under the head of the rail.

18. A rail clip according to any one of the preceding claims wherein, the clip is made of metal.

19. A rail clip according to claim 18 wherein, the clip is made of steel.

20 20. A rail clip according to claim 18 or claim 19 wherein, the clip is painted or treated to resist corrosion,

21. A rail clip for resisting movement of a rail in an emergency when the rail is subjected to higher than normal loads, the clip having first and 25 second stops normally spaced from the rail in an inoperative condition of the clip and being arranged to engage a web and base respectively of the rail in an operative condition of the clip, and means for adjusting the position of each stop to vary the size of a clearance gap between each stop and the rail in the inoperative condition.

14

22. A rail clip substantially as hereinbefore described with reference to Figures I and 2 of the accompanying drawings.

23. A rail clip substantially as hereinbefore described with reference to 5 Figures 3A and 5 of the accompanying drawings.

24. A rail assembly including an elongate rail having a head, a base and a web connecting the head and base, and at least one pair of rail clips arranged on opposite sides of the rail to restrict movement of the rail in an emergency, each rail clip having first and second stops normally spaced from the rail in an inoperative condition of the clip and being arranged to engage a web and base respectively of the rail in an operative condition of the clip.

25. A rail assembly according to claim 24 further including means for locating the rail in the inoperative condition of the rail clips.