IE86541B1

IE86541B1 - A clamp

Info

Publication number: IE86541B1
Application number: IE20130253A
Authority: IE
Inventors: Anthony Hanlon
Original assignee: Anthony Hanlon
Priority date: 2013-08-26
Filing date: 2013-08-26
Publication date: 2015-06-03
Also published as: IE20130253A1; GB201415066D0; GB2518751B; GB2518751A

Abstract

A clamp [1] for retaining an object (9) in position, the clamp comprising a support member (3); a retaining member (19) for retaining the object, the retaining member being movably mounted on the support member; a fixing arrangement (37) for fastening the support member to a surface; a stop means (33) for fixing the retaining member in a clamping position in which the retaining member prevents the object from moving. <Figure 1>

Description

A Clamp Field of the Invention The present invention provides a clamp. More specifically, there is provided a clamp for retaining in position an object, such as, for example, but not limited thereto, a portion of a vaive, such as a valve of an underground pipeline.

Background to the Invention Underground pipelines, such as, for example, gas mains, need to be accessed from time to time for various reasons, such as, for example, for maintenance or repair. To gain access to the pipeline, excavation works often need to be carried out. Typically, pipelines include various valves. Some valves have covers, or valve heads, held in place by bolts. These bolts wear over time and need to be replaced regularly. If the bolts fail during replacement the valve head may become displaced under pipeline pressure and injure a worker and/or cause other harm.

A known technique to avoid a valve malfunction related accident during bolt replacement is to install a temporary bypass conduit bypassing the valve in the section of the pipeline to be inspected. This necessarily involves interrupting flow in the pipeline for the duration of installation of the bypass conduit and conducting extra excavation work to accommodate the bypass conduit. Once a bypass conduit has been installed, flow is resumed through the bypass conduit allowing the isolated pipeline section to be inspected. This technique is laborious, time consuming, and therefore costly, as well as disruptive for consumers.

The inventor has appreciated the need for an improvement in the pipeline excavation safety technique.

Accordingly, the object of the present invention is to provide a means for preventing valve failure during pipeline excavation without interrupting the pipeline.

P161529.IE.01 Summary of the Invention According to a first aspect of the present invention there is provided a clamp for use in pipeline maintenance for retaining an object in position in a recess, the clamp comprising a support member; a retaining member for retaining the object, the retaining member being movably mounted on the support member; a fixing arrangement for fastening the support member to a surface about an opening of the recess; a stop means for fixing the retaining member in a clamping position in which the retaining member prevents the object from moving.

The support member is adapted to be positioned above the object to be clamped about the opening of the recess in a surface, the recess containing the object, and, across the opening of the recess. The surface may be any surface, such as, for example soil, concrete, asphalt and other. The retaining member is lowered onto the object from a position above the object. Preferably, the retaining member is lowered into the recess to clamp the object.

Preferably, the support member comprises a crossbar having a pair of opposite ends. Preferably, the crossbar is adapted to be positioned across the opening of the recess such that the opposite ends rest on a surface and a central part of the crossbar extends across the opening of the recess.

Preferably, the fixing arrangement is adapted to fasten the support member to the surface about the recess. in on arrangement, the retaining member comprises a pole. The pole may be a threaded pole and the support member may have a corresponding threaded through aperture so that rotation of the pole in the through aperture causes the pole to advance linearly with respect to the support member. The stop means for fixing the retaining member in a clamping position may comprise a lock nut having an internal thread cooperating with the thread of the pole, wherein when the lock nut is threaded on the pole and tightened at the support member so that the pole and the support member become mutually fixed. Ρ161Ξ29.ΙΕ.01 In one arrangement, the support member and the retaining member have substantially perpendicular longitudinal axes when assembled.

The retaining member has a retaining end for contacting the object in the clamping 5 position. The retaining end is adapted to be lowered onto the object from a position above the object. Preferably, the retaining end includes a retaining head larger in cross section than the rest of the retaining member. Preferably, the retaining end includes a cushioning means to reduce wear and to provide for a better grip between the retaining end and the object. The cushioning means may comprise a resiliently deformable pad, for example, an elastomeric pad, e.g. a natural or synthetic rubber pad.

Preferably, the retaining member includes a lever for moving the retaining member with respect to the support member. In the embodiment including the cooperating threaded pole and aperture, the lever may be a rotary lever for rotating the pole in the aperture.

In one variation, the fixing arrangement comprises retainers for fixing the support member to a surface. The retainers may include fasteners, such as, for example bolts or pins, weights or a combination thereof. If the surface is relatively soft ground, weight plates with studs can be installed over the support member and weights can placed on these plates to provide extra weight where necessary to fasten the support member in place. In one arrangement, a weight plate can be installed over the support member and a weight with a laterally protruding bracket can be provided for holding down the weight plate. The weight plate can include an upstanding rod and the bracket can be threaded on the rod while the weight is being located on or near the weight plate. A second weight can be used to increase the weight on the weight plate. The second weight can be turned upside down in relation to the first weight to allow the bracket of the second weight to be stacked on the bracket of the first weight.

The fixing arrangement may further comprise a pair of arms, each arm being attached, preferably hingedly, e.g. by means of a pivot pin, to one of the opposite ends of the crossbar and the retainers are adapted to fix the arms to the surface. A locking member may be provided for preventing the arm from pivoting about the support member when the arm has been fixed to the surface. The locking member may comprise a locking pin. Each arm is preferably arranged to pivot between an extended position in which the arm can be fastened to the surface and a folded position in which the arm is folded towards the crossbar for storage or transportation. In one arrangement, in the extended position, the arm is substantially collinear with the crossbar. In one arrangement, in the folded position, the arm is substantially perpendicular to the crossbar or positioned at an acute angle to the cross bar. A locking arrangement may be provided for holding the arms in the folded position. The arms may include cushioning means, such as, for example, elastomeric pads, to improve grip between the arm and the surface to which the arms are being fastened.

The object may be a valve, or a valve head. The object may be positioned underground. The valve may be that of an underground pipeline. The recess may be an access bore formed in the ground to access the object A preferred use of the clamp of the invention is to secure a valve head of a valve of an underground pipeline to prevent the valve head from lifting accidentally and the contents ofthe pipeline from escaping during excavation, e.g. due to failure of vaive head retaining bolts.

The clamp of the invention renders pipeline excavation works safe as well as time- and cost-efficient. Because the valve head is being held down securely, the valve can remain open and therefore there is no need to install a bypass conduit and interrupt the flow in the pipeline. A further advantage of the clamp of the invention is that its configuration is such that access to the valve and the pipeline is not obstructed when the clamp is fixed in position thereby allowing the valve and the pipeline to be serviced. it will be appreciated that, although the invention has been provided for the purpose of securing a valve head of a valve of an underground pipeline for preventing the valve head from lifting during excavation, the present invention is indeed suitable for clamping other objects whether located in recesses or on surface.

P161529.IE.01 According to a second aspect there is provided a method of retaining an object in position in a recess in pipeline maintenance, the method comprising the steps of providing a clamp according the first aspect of the invention; fastening the support member of the clamp to a surface using the fixing arrangement; moving the retaining member relative to the support member into a clamping position in which the retaining member prevents the object from moving; and fixing the retaining member in the clamping position by the stop means.

Preferably, the method comprises the step of forming a recess in the surface prior to installing the clamp in order to access the object. The recess may be an access bore.

The method comprises the step of positioning the support member above the object to be clamped, about the opening of the recess, and across the opening of the recess.

The method comprises the step of lowering the retaining member onto the object from a position above the object to clamp the object. The retaining member is lowered into the recess to clamp the object.

Preferably, the method comprises the step of positioning the crossbar of the support member across the opening of the recess such that the opposite ends of the crossbar rest on the surface and a central part of the crossbar extends across the opening of the recess.

In one arrangement, the method comprises the step of rotating the pole in the threaded through aperture of the support member causing the pole to advance linearly with respect to the support member. The method preferably further comprises the step of threading the lock nut on the pole and tightening the lock nut at the support member so that the pole and the support member become mutually fixed.

Preferably, the step of fastening the support member to a surface includes pivoting the arms of the fixing arrangement relative to the crossbar into an extended position and fixing the arms to the surface by retainers. The method may further include the step of P161529.IE.01 using a respective locking member to prevent each arm from pivoting about the support member when the arm has been fixed to the surface.

The method may further include the step of releasing the arms from the surface and folding the arms towards the crossbar for storage or transportation and, preferably, keeping the arms in the folded position using a locking arrangement.

All essential, preferred or optional features or steps of the second aspect of the invention can be provided in conjunction with the features of the first aspect of the invention and vice versa where appropriate.

Accordingly, the invention provides a clamp for use in pipeline maintenance for 10 retaining an object in position in a recess and a corresponding method, as defined in the appended claims.

Detailed Description of the Invention Exemplary embodiments of the invention will now be described in more detail 15 with reference to the accompanying drawings. In the drawings: Figure 1 is a front view of the clamp of the invention in a clamping mode; Figure 2 is a front view of the clamp of the invention in a partially folded mode; Figure 3 is a front view of the clamp of the invention in a folded mode; Figure 4 is a side perspective view of the clamp of the invention in a folded mode; and Figure 5 is schematic partial perspective view of an alternative fastener of the clamp of the invention.

It will be appreciated that although a preferred use of the clamp of the invention is to 25 secure a valve head of a valve of an underground pipeline to prevent the valve head from lifting accidentally and the contents of the pipeline from escaping during excavation, e.g. due to failure of valve head retaining bolts, the present invention is indeed suitable for clamping other objects whether located in recesses or on surface. Referring initially to Figure 1, a clamp for retaining an object in position in accordance with the invention is 30 indicated generally by reference numeral 1. In the presently described embodiment, the object is a valve head 9 of a vaive 11 of an underground pipeline 15. An access bore 17 is formed in the ground in order to access the valve 11 and the pipeline 15. The clamp 1 of the invention is then used to secure the valve head 9 in Ί place to prevent the valve head 9 from lifting accidentally and the contents of the pipeline from escaping during excavation, e.g. due to failure of valve head retaining bolts (not shown). Once secured by the clamp 1, the valve 11 can remain open during further works and therefore there is no need to install a bypass conduit and interrupt the flow in the pipeline 15.

The clamp 1 comprises a support member provided in the form of a crossbar 3 having a pair of opposite ends 5, 7. In use, the crossbar 3 is positioned above the valve head 9 to be clamped so that the opposite ends 5, 7 of the crossbar 3 rest on a surface surrounding an opening 18 of the access bore 17 and a central part (not indicated by a numeral) of the crossbar 3 extends across the opening 18. The surface surrounding the opening 18 may be any surface such as, for example, soil, concrete, asphalt and other.

The clamp 1 further comprises a retaining member provided in the form of a threaded pole 19 for retaining the valve head 9 in place. The pole 19 is movably mounted on the crossbar 3. The crossbar 3 has a corresponding threaded through aperture (not visible in the drawings) for receiving the pole 19 so that longitudinal axes of the crossbar 3 and the pole 19 are substantially perpendicular when the crossbar 3 and the pole 19 are assembled. In the present embodiment the corresponding threaded through aperture is provided in a welded nut 21, although it will be appreciated that the threaded through aperture can also be provided directly in the crossbar 3.

Rotation of the pole 19 in the through aperture of the crossbar 3 causes the pole 19 to advance linearly with respect to the crossbar 3 towards the valve head 9 as indicated by arrow 23 in Figure 1.

The pole 19 has a retaining end 27 for clamping the valve head 9. The retaining end 27 includes a retaining head 29 larger in cross section than the rest of the pole 19. The retaining head 29 is lowered into the recess 17 to clamp the valve head 9 from a position above the valve head 9. The retaining head 29 includes a cushioning means in the present embodiment provided in the form of an elastomeric pad 31 to reduce wear and to provide for a better grip between the retaining head 29 and the valve head 9.

The pole 19 includes a rotary lever 25 at an end of the pole 19 opposite the retaining end 27 of the pole 19 for rotating the pole 19 in the corresponding threaded aperture of the crossbar 3.

The clamp 1 comprises a stop means for fixing the pole 19 in a clamping position in which the pole 19 prevents the valve head 9 from moving. In the present embodiment, the stop means for fixing the pole 19 in a clamping position comprises a lock nut 33 having an internal thread (not visible in the drawings) cooperating with the thread of the pole 19. When the retaining head 29 of the pole clamps the valve head 9, the lock nut 33 is threaded on the pole 19 and tightened at the crossbar 3 so that the pole 19 and the crossbar 3 become mutually fixed.

The clamp 1 further includes a fixing arrangement for fastening the crossbar 3 to the surface surrounding the access bore 17. In the presently described embodiment, the fixing arrangement comprises a pair of arms 35 and retainers provided in the present embodiment in the form of bolts 37 for fixing the arms 35 to the surface. Each arm 35 is hingedly attached to one of the opposite ends 5, 7 of the crossbar 3 by means of a pivot pin 10. Each arm 35 is arranged to pivot between an extended position (as in Figure 1) in which the arm 35 is fastened to the surface and a folded position (as in Figures 3 and 4) in which the arm 35 is folded towards the crossbar 3 for storage or transportation. In the extended position, the arm 35 is substantially collinear with the crossbar 3. A locking member in the form of a locking pin 12 is provided for preventing the arm 35 from pivoting about the crossbar 3 when the arm 35 has been fixed to the surface. In the folded position, the arm 35 is substantially perpendicular to the crossbar 3. A locking arrangement in the form of chain 39 (Figures 2 to 4) is provided for holding the arms 35 in the folded position. The arms 35 are provided with cushioning means in the form of elastomeric pads 40 to improve grip between the arms 35 and the surface to which the arms 35 are fastened. If the surface is soft ground, as shown in Figure 5, a weight plate 50 can be installed over the arms 35 and a weight 51 with a laterally protruding bracket 53 can be provided for holding down the plate 50. The plate 50 can include an upstanding rod 55 and the bracket 53 can be threaded on the rod 55 while the weight 51 is being located on or near the weight plate 50. A second weight 51 (not shown) can be used to increase the weight on the weight plate 50. The second weight 51 can be turned P161529.IE.01 upside down in relation to the first weight 51 to allow the bracket 53 of the second weight 51 to be stacked on the bracket 53 of the first weight 51.

In use, in order to clamp 1 a valve head 9 of a valve 11 of an underground pipeline 15, an 5 access bore 17 is formed in the surface prior to installing the clamp 1 in order to access the valve 11. The crossbar 3 of the clamp 1 is then positioned across the opening 18 of the access bore 17 such that the opposite ends 5, 7 of the crossbar rest 3 on the surface and a central part of the crossbar extends 3 across the opening 18 above the valve 11.

In order to fix the crossbar 3 to the ground, the arms 35 are pivoted relative to the crossbar 3 into an extended position, locked by pins 12 to the cross bar 3 to prevent each arm 35 from pivoting about the crossbar 3 and fixed to the surface by the bolts 37.

The pole 19 is then rotated in the threaded through aperture of the crossbar 3 causing the pole 19 to advance linearly with respect to the crossbar 3 thereby lowering the retaining head 29 onto the valve head 9 into a clamping position in which the retaining head 29 prevents the valve head 9 from moving. The pole 19 is then fixed in the clamping position by tightening the lock nut 33 on the pole 19 at the crossbar 3 so that the pole 19 and the crossbar 3 become mutually fixed.

In order to remove the clamp 1, the bolts 37 are removed and the arms 35 are released from the surface. The arms 35 are then folded towards the crossbar 3 and secured in the folded position by the chain 39 for storage or transportation.

The clamp 1 of the invention renders pipeline excavation works safe as well as time- and cost-efficient. Because the valve head 9 is being held down securely, the valve 11 can remain open and therefore there is no need to install a bypass conduit and interrupt the flow in the pipeline 15. A further advantage of the clamp 1 of the invention is that its configuration is such that access to the valve 11 and the pipeline 15 is not obstructed when the clamp is fixed in position thereby allowing the valve 11 and the pipeline 15 to be serviced.

Modifications are possible within the scope of the present invention as defined in the appended claims.

Claims

1. A clamp for use in pipeline maintenance for retaining an object in position in a recess, the clamp comprising a support member; a retaining member for retaining the object, the retaining member being movably mounted on the support member; a fixing arrangement for fastening the support member to a surface about an opening of the recess; a stop means for fixing the retaining member in a clamping position in which the retaining member prevents the object from moving; wherein the support member is adapted to be positioned across the opening of the recess in a surface and above the object to be clamped; wherein the retaining member has a retaining end for contacting the object in the clamping position; wherein the retaining end is adapted to be lowered onto the object from a position above the object; and wherein in the clamping position the retaining end is located in the recess below the surface to which the support member is fastened.

2. A clamp as claimed in claim 1, wherein the support member comprises a crossbar having a pair of opposite ends.

3. A clamp as claimed in claim 2, wherein the crossbar is adapted to be positioned across the opening of the recess with the opposite ends resting on the surface about the opening of the recess and a central part of the crossbar extending across the opening of the recess.

4. A clamp as claimed in any preceding claim, wherein the retaining member comprises a pole. 5. Of providing the retaining member in the form of a pole and rotating the pole in a threaded through aperture of the support member causing the pole to advance linearly with respect to the support member. 37. A method of claim 36, wherein the method comprises the step of threading a 10 lock nut on the pole and tightening the lock nut at the support member so that the pole and the support member become mutually fixed. 38. A method of claim 35, wherein the step of fastening the support member to the surface includes pivoting arms of the fixing arrangement relative to the crossbar 5 a retaining member for retaining the object, the retaining member being movably mounted on the support member; a fixing arrangement for fastening the support member to a surface about an opening of the recess; and a stop means for fixing the retaining member in a clamping position in which 5 preventing the arm from pivoting about the support member when the arm has been fixed to the surface.

5. A clamp as claimed in any preceding claim, wherein the pole is a threaded pole and the support member has a corresponding threaded through aperture so that rotation of the pole in the through aperture causes the pole to advance linearly with respect to the support member.

6. A clamp as claimed in any preceding claim, wherein the stop means for fixing the retaining member in a clamping position comprises a lock nut having an internal thread cooperating with the thread of the pole, wherein when the lock nut is threaded on the pole and tightened at the support member so that the pole and the support member become mutually fixed.

7. A clamp as claimed in any preceding claim, wherein the support member and the retaining member have substantially perpendicular longitudinal axes when assembled.

8. A clamp as claimed in any preceding claim, wherein the retaining end includes a retaining head larger in cross section than the rest of the retaining member.

9. A clamp as claimed in any preceding claim, wherein the retaining end includes a cushioning means to reduce wear and to provide for a better grip between the retaining end and the object. 10. The retaining member prevents the object from moving; wherein the retaining member has a retaining end for contacting the object in the clamping position; - positioning the support member across the opening of the recess in a surface and above the object to be clamped; -fastening the support member of the clamp to the surface using the fixing 10 over the support member,

10. A clamp as claimed in claim 9, wherein the cushioning means comprises a resiiientiy deformable pad.

11. A clamp as claimed in any preceding claim, wherein the retaining member includes a lever for moving the retaining member with respect to the support member.

12. A clamp as claimed in claim 11, wherein the lever is a rotary lever.

13. A clamp as claimed in any preceding claim, wherein the fixing arrangement comprises retainers for fixing the support member to the surface.

14. A clamp as claimed in claim 13, wherein the retainers include fasteners. 15. Into an extended position and fixing the arms to the surface by retainers. 39. A method of claim 38, wherein the method includes the step of using a respective locking member to prevent each arm from pivoting about the support member when the arm has been fixed to the surface. 40. A method of claim 38 or 39, wherein the method includes the step of releasing the arms from the surface and folding the arms towards the crossbar. 41. A method of claim 40, wherein the method includes the step of keeping the 15 arrangement; -moving the retaining member relative to the support member into a clamping position in which the retaining member prevents the object from moving including lowering the retaining end into the recess onto the object from a position above the object to clamp the object; and

15. A clamp as claimed in claim 14, wherein the fasteners include bolts or pins or weights or a combination thereof.

16. A clamp as claimed in any preceding claim, wherein a weight plate is installed

17. A clamp as claimed in claim 16, wherein a weight is provided for holding down the weight plate. 15

18. A clamp as claimed in claim 17, wherein the weight has a laterally protruding bracket.

19. A clamp as claimed in claim 18, wherein the weight plate includes an upstanding rod and the bracket is adapted to be threaded on the rod while the 20. -fixing the retaining member in the clamping position by the stop means wherein the retaining end is located in the recess below the surface to which the support member is fastened. 33. A method of claim 32, wherein the method comprises the step of forming a 20 arm is substantially perpendicular to the crossbar or positioned at an acute angle to the cross bar.

20. A clamp as claimed in any one of claims 17 to 19, wherein a second weight is provided to increase the weight on the weight plate. 25 20 weight is being located on or near the weight plate.

21. A clamp as claimed in claim 20, wherein on assembly the second weight is turned upside down in relation to the first weight and wherein the bracket of the second weight is stacked on the bracket of the first weight.

22. A clamp as claimed in claim 2 or claim 3, wherein the fixing arrangement 30 comprises a pair of arms, each arm being attached to one of the opposite ends of the crossbar and the retainers are adapted to fix the arms to the surface.

23. A clamp as claimed in claim 22, wherein each arm is hingedly attached to one of the opposite ends of the crossbar.

24. A clamp as claimed in claim 23, wherein a locking member is provided for 25. Arms in the folded position using a locking arrangement. 42. A clamp substantially as herein described with reference to and as shown in the accompanying drawings. 25 recess in the surface prior to installing the clamp in order to access the object. 34. A method of claim 33, wherein the recess comprises an access bore. 35. A method of any one of claims 32 to 34, wherein the method comprises the step 30 of providing the support member in the form of a crossbar and positioning the crossbar of the support member across the opening of the recess such that the opposite ends of the crossbar rest on the surface about the opening of the recess and a central part of the crossbar extends across the opening of the recess. 36. A method of any one of claims 32 to 35, wherein the method comprises the step

25. A clamp as claimed in claim 24, wherein the locking member comprises a locking pin.

26. A clamp as claimed in any one of claims 23 to 25, wherein each arm is arranged to pivot between an extended position in which the arm can be fastened to the surface and a folded position in which the arm is folded towards the crossbar for storage or transportation.

27. A clamp as claimed in claim 26, wherein in the extended position the arm is substantially collinear with the crossbar.

28. A clamp as claimed in claim 26 or claim 27, wherein in the folded position, the

29. A clamp as claimed in any one of claims 26 to 28, wherein a locking arrangement is provided for holding the arms in the folded position. 30. A clamp as claimed in any one of claims 22 to 29, wherein the arms include cushioning means to improve grip between the arm and the surface to which the arms are being fastened. 30 31. A clamp as claimed in any preceding claim, wherein the object comprises a valve, or a valve head. 32. A method of retaining an object in position in a recess in pipeline maintenance, the method comprising the steps of -providing a clamp comprising a support member;

30. 43. A method substantially as herein described with reference to the accompanying drawings.