GB2459533A

GB2459533A - Composite support slab for use as ground interface for stabilising outrigger feet

Info

Publication number: GB2459533A
Application number: GB0807875A
Authority: GB
Inventors: Lee Galloway
Original assignee: International Pipeline Products Ltd
Current assignee: International Pipeline Products Ltd
Priority date: 2008-04-30
Filing date: 2008-04-30
Publication date: 2009-11-04
Also published as: GB0807875D0

Abstract

The support slab, generally used as an accessory for stabilizers of cranes, mobile platforms, aerial platforms and the like equipment, has a composite construction with a first element 5 of a first foamed material of relatively lighter weight, and a second element 9 of a second, different, generally more rigid material. The first and second elements are slabs, the first slab 5 typically formed of polyurethane in rigid foam form, and the second slab 9 formed of polyurethane in a non-foam form. The slab may also have a sandwich construction with the foamed layer 5 surrounded by a thin layer of sold material 15 and may also be provided with a handle.

Description

IMPROVEMENTS IN AND RELATING TO SUPPORT SURFACES

This invention concerns improvements in and relating to support elements, particularly for use as support elements for outriggers used to brace equipment.

A variety of items of equipment use braces to help stabilise them when in use. The braces often have a stowed position during movement of the equipment and a deployed position during bracing of the equipment. Cranes, mobile platforms, aerial platforms and the like all frequently make use of such braces.

Because the ground surface at the location of use is often not capable of bearing heavy loads, it is common practice to use support elements in the form of outrigger pads. These increase the area over which the load from the outrigger is dispersed to the ground.

The present invention has amongst its aims to provide an improved form of support element, particularly outrigger pad. The present invention may include amongst its aims the provision of support elements which offer the necessary load bearing capacity, but are lighter in weight than previous designs.

:According to a first aspect of the invention there is provided a support element, the support *...

* being formed from a first element of a first material and a second element of a i.:' : second, different, material.

* The support element may include a first planar element. The support element may include a * second planar element. The first planar element may be provided on the second planar * * ,element. The first element and second element may have the same width and!or length and/or radius as the other. The width and/or length and/or radius may be considered in the plane of the largest surface of the support element and/or ground surface and/or surface of the brace which engages the support element. The first and second planar elements may each be a slab.

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The support element may include a first planar element. The support element may include one or more second elements. The one or more second elements may be provided on the first element, for instance, with one second element provided on a first element surface, in respect of one or more or all the first element surfaces. The second element may be a layer provided on the first element. The layer may cover the whole or part of one or more of the surfaces of the first element. Preferably the layer covers all the surfaces of the first element. A continuous layer may be provided on the first element. The first element may be coated with the second element.

The first element may be provided with an external surface which contacts the environment of the support element. The external surface may be adapted to engage a brace engaging component in use. The first element may be provided with an internal surface which contacts the second element.

The first element may be provided without an external surface which contacts the environment of the support elenient. The first element may be provided with an internal surface which contacts the second element. Preferably all of the surfaces of the first element are internal surfaces.

The first material may comprise or consist of polyurethane. The first material may be * : olyurethane in rigid foam form. The first material may be a cross-linked polyether based * ioliurethane. The first material may be produced from polyether polyols. The first material : may include polyethylene glycol segments. *.*

* The first material may have a density of 100 to 750 kg.m3. The first material may have a -3 -3 *,.1.density of 150 to 600 kg.m. The first material may have a density of 250 to 550 kg.m * * ,The first material may have a density greater than 100 kg.m3. The first material may have a density greater than 150 kg.m3. The first material may have a density greater than 175 kg.m3.

The first material may have a density greater than 200 kg.m3. The first material may have a density greater than 250 kg.m3. The first material may have a density of less than 1000 kg.m . The first material may have a density of less than 900 kg.m3. The first material may have a density of less than 750 kg.m3. The first material may have a density of less than 600 kg.m3.

The first material may have a density of less than 550 kg.m3.

The first element may have a thickness of 2 to 20 cm. The first element may have a thickness of 4 to 15 cm. The first element may have a thickness of 5 to 12 cm. The first element may have a thickness of 6 to 8 cm. The first element may have a minimum thickness of 2 cm. The first element may have a minimum thickness of 3 cm. The first element may have a minimum thickness of 4 cm. The first element may have a minimum thickness of 5 cm. The first element may have a maximum thickness of 20 cm. The first element may have a maximum thickness of 16 cm. The first element may have a maximum thickness of 10 cm. The first element may have a maximum thickness of 9 cm. The thickness may be considered perpendicular to the largest surface of the support element and/or ground surface and/or surface of the brace which engages the support element.

The second element may be provided with an external surface. The external surface may be adapted to engage the ground, in use. The second element may be provided with an internal surface which contacts the first element.

The second element may provide all the external surfaces which contacts the environment of the support element. The second element may be provided with an internal surface which * ontacts the second element. S... * . S...

The second material may by of polyurethane. The second material may be polyurethane in * non-foam form. The second material may have a density of 800 to 1750 kg.m3. The second S..

* material may have a density of 850 to 1500 kg.m3. The second material may have a density 900 to 1300 kg.m3. The second material may have a density of 1000 to 1200 kg.m* The econd material may have a density greater than 800 kg.m3. The second material may have a density greater than 850 kg.nf3. The second material may have a density greater than 900 kg.m3. The second material may have a density greater than 950 kg.m3. The second material may have a density of less than 1500 kg.m3. The second material may have a density of less than 1350 kg.m3. The second material may have a density of less than 1300 kg.m3. The second material may have a density of less than 1200 kg.m3.

The second element may have a thickness of 0.2 to 5 cm. The first element may have a thickness of 0.4 to 4 cm. The first element may have a thickness of 0.6 to 3 cm. The first element may have a thickness of 0.75 to 2.5 cm. The first element may have a minimum thickness of 0.2 cm. The first element may have a minimum thickness of 0.4 cm. The first element may have a minimum thickness of 0.6 cm. The first element may have a minimum thickness of 0.8 cm. The first element may have a maximum thickness of 6 cm. The first element may have a maximum thickness of 4 cm. The first element may have a maximum thickness of 3 cm. The first element may have a maximum thickness of 2.5 cm. The thickness may be considered perpendicular to the largest surface of the support element and/or ground surface and/or surface of the brace which engages the support element. The thickness values of this paragraph may particularly apply where the support element is formed of a first planar element and second planar element.

The second element may have a thickness of 0.1 to 1 cm. The first element may have a thickness of 0.15 to 0.6 cm. The first element may have a thickness of 0.15 to 0.4 cm. The first element may have a thickness of 0.15 to 0.25 cm. The first element may have a minimum thickness of 0.1 cm. The first element may have a minimum thickness of 0.15 cm.

The first element may have a minimum thickness of 0.1175 cm. The first element may have a minimum thickness of 0.2 cm. The first element may have a maximum thickness of 1 cm.

The first element may have a maximum thickness of 0.6 cm. The first element may have a *:::maximum thickness of 0.4 cm. The first element may have a maximum thickness of 0.25 cm.

* The thickness may be considered perpendicular to the largest surface of the support element * ** andlor ground surface and/or surface of the brace which engages the support element. The thickness values of this paragraph may particularly apply where the support element is formed S..

* of a first element with the second element provided as a coating thereon. * .* * U * * .*

The support element may have a weight of less than 70% the weight of a slab of equivalent volume made of polyurethane in non-foam form. The support element may have a weight of less than 50% the weight of a slab of equivalent volume made of polyurethane in non-foam form. The support element may have a weight of less than 40% the weight of a slab of equivalent volume made of polyurethane in non-foam form. The support element may have a weight of less than 30% the weight of a slab of equivalent volume made of polyurethane in non-foam form. The support element may have a weight of less than 25% the weight of a slab of equivalent volume made of polyurethane in non-foam form.

The first element may be bonded to the second element. The bond may be formed by one or more parts of the second element entering one or more recesses in the first element.

The support structure may be provided with one or more handles. The one or more handles may have a fixed configuration or have a flexible configuration. The one or more handles may be of rope or chain. One or more handles may be embedded in the first element or in the second element or in both the first element and second element, for instance at the interface between the two elements.

One or more of the first element or second element may be pigmented.

The support element may have a square profile. The support element may have a length and/or width of greater than 3 0cm. The support element may have a length and/or width of less than 150 cm.

The support element may have a circular profile. The support element may have a radius of greater than 3 0cm. The support element may have a radius of less than 100cm. * S * ** * * *** * *

* :* According to a second aspect of the invention we provide a method of bracing equipment, the method comprising: S..

providing a support element between a component of the equipment and the ground; * * bringing the component into contact with the support element, the support element * * being in contact with the ground, the support element being formed from a first element of a first material and a second element of a second, different, material.

One or more of the support elements may include any of the features, options or possibilities set out elsewhere in this document, particularly in the first aspect of the invention.

The equipment may be provided according to any of the features, options or possibilities set out elsewhere in this document, particularly in the third aspect of the invention.

Preferably the method includes providing at least two, more preferably at least four, support elements, each being provided between a separate component of the equipment and the ground. preferably the method further includes, for each support element, bringing the component into contact with the support element, the support element being in contact with the ground.

The method may include varying the centre of gravity of the equipment, once the equipment is braced.

According to a third aspect of the invention we provide a kit, the kit comprising: equipment, the equipment preferably has a centre of gravity which is variable and one or more bracing components; and one or more support elements, one or more of the support elements being formed from a first element of a first material and a second element of a second, different, material.

One or more of the support elements may include any of the features, options or possibilities *. : set out elsewhere in this document, particularly in the first aspect of the invention. *... * I *I.*

1:' :* Preferably the kit includes at least one support element for each bracing component provided on the equipment. The kit may include two or more support elements. The kit may include :::: four or more support elements.

*.: The equipment may be a crane, particularly a mobile crane. The equipment may have an extendable component. The extendable component may be an arm. The extendable component may be extended by changing its length and/or by changing its elevation. The extendable component may be the support for a platform. The equipment may be an aerial access device, The centre of gravity may be varied due to variations in the extendable component position andlor configuration andlor load acting thereon.

The equipment may be provided with two or more bracing components. Preferably four or more bracing components are provided. One or more of the bracing components may have a first position and a second position. The first position may be a stowed position. The second position may be a deployed position.

One or more of the support elements may be provided between a brace component and the ground. The brace component may engage the upper surface of the support element andlor the ground may engage the ground.

Various embodiments of the invention will now be described, by way of example only, and with reference to the accompanying drawings in which: Figure 1 is a side cross-sectional view through one outrigger pad according to the present invention; and Figure 2 is a side cross-sectional view through a second outrigger pad according to the present invention. * ***

.. : When a crane is being driven to a location of use, the crane arm is retracted and lowered.

* * hence the centre of gravity for the crane is low. When in use, however, the crane arm is * * elevated and extended. The increases the height of the centre of gravity and causes leverage , type forces to arise. To counteract this, it is known to provide braces for the crane. These * increase the separation between the support locations for the crane. Instead of the support locations being the wheels used to move the crane, at say 2m spread, the braces can extend *.outward from the crane and raise the separation up to 6m or higher. The braces typically extend to the side of the crane and in front of the crane to varying degrees.

The braces generally have a stowed position during movement of the crane so as to minimise the overall dimensions of the crane. The braces also have a deployed position during bracing of the equipment, with a far greater overall dimension for the crane as a result. The transition from stowed to deployed position may be provided through one or more of telescopic, rotational and elevational movements.

Cranes, equipment incorporating a platform which can be lowered and raised and a variety of other such equipment make use of such braces. They are frequently referred to as outriggers.

Cranes and such devices need to be used at a wide variety of different locations and hence on a wide variety of different ground types. These ground types can vary significantly in their load bearing characteristics. As a consequence, there is a need to spread the load from the brace over a large area to ensure that the ground can cope with the level of loading and not deform. If the ground deforms under the brace, the crane can start to tilt and become unstable.

In an extreme example, the crane could topple over.

To counteract this, the brace seeks to contact the ground over a large area. this is performed using support elements which are not connected to the braces. In that way, the area of the support elements can be large, without having to be accommodated on the crane at the position of the brace. Typically, the support elements are mounted on the crane, over the chassis where there is free space.

A variety of support elements or outrigger pads are known. In the case of steel plates, these * . . : offer good load bearing properties, but are heavy to put in place and have significant value as S...

* * . scrap making them vulnerable to theft. Other forms, such as wooden plates or railway are also heavy, and have durability problems. S..

* It is known to use slabs of polyethylene or of polyurethane to form such support elements.

* . These are formed of a single type of polyethylene or polyurethane. They are able to cope with loads well, but are also very heavy.

The weight of the support elements is a particular issue in this context as the crane is often driven, set up, used and dismantled by a single person. This places a limit on the weight of a single support element that can be used comfortably by one person and/or due to health and safety limitations on the weight one person can be expected to lift. Such a limit would be around 60kg, but varies from country to country, The present invention provides a series of improved and lighter weight support elements through the use of composite materials.

In the first embodiment of the invention shown in Figure 1, the support element 3 is provided formed from two separate slabs.

The first slab 5 is intended to be the brace engaging slab and so has a brace engaging surface 7. This first slab 5 is formed of polyurethane in rigid foam form. The polyurethane in rigid foam form typically has a density of 200 to 500 kg.m3. The first slab 5 may have a thickness of 6 to 8 cm.

The second slab 9 is intended to be the ground engaging slab and so has a ground engaging surface 11. This second slab 9 is formed of polyurethane. The second slab polyurethane typically has a density of 1000 to 1200 kg.m3. The second slab 5 may have a thickness of 1 to 2 cm.

A structure of this type has been found to have the necessary load bearing capacity for its size.

* : Furthermore, the second slab 9 provides sufficient resistance to damage from contacting the *s,e ". potentially rough ground. At the same time, the overall support element 3 is roughly 20% of * the weight of the pure polyurethane form.

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During production, the first slab 5 is formed in a mould and, once hardened, the second slab 9 is formed by pouring the polyurethane on top of the first slab 5. Both are then allowed to . harden completely. A natural bond forms between the two slabs. The ability to form this bond can be increased by roughing the interface surface 13 of the first slab 9 before the second slab 5 is poured on.

It is possible to mould fixed form or flexible form handles (not shown) into one or more edges of the support element 3. These can be embedded in the first slab 5 andlor second slab 9, for instance by positioning them correctly prior to introducing the slab material, the handles are retained in the slabs once they have hardened.

In the second embodiment shown in Figure 2, the first slab 5 is used as the core of the support element 3. This has the same general material properties described above. The first slab 5 may be 4 to 8cm thick. Once the first slab 5 has been moulded the second material layer 15 may be provided around it. The second material layer 15 is formed of generally the same material as described above for the second slab 9. The second material layer 15 may be applied by moulding or more preferably by spraying the second layer material 15 on. The second material layer may have a thickness of 1 to 5mm. As shown, the second material layer is applied to all surfaces.

It is possible to apply a variety of pigments to one or more of the first slab, second slab or second material layer.

A wide variety of sizes, shapes and thicknesses for the support elements can be provided using this approach to suit a variety of situations and equipment needing support elements. * I ** a * a* a I a, * It * I S

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Claims

CLAIMS1. A support element, the support element being formed from a first element of a first material and a second element of a second, different, material.
2. A support element as claimed in claim 1, wherein the support element includes a first planar element and a second planar element, the first planar element provided on the second planar element.
3. A support element as claimed in claim 2, wherein the first and second planar elements have the same width and length.
4. A support element as claimed in claim 1, wherein the support element includes a first planar element and a second element, the second element being a layer provided on the first element.C
5. A support element as claimed in claim 4, in which the layer covers at least part of C one or more of the surfaces of the first element. Co
6. A support element as claimed in claim 5, in which the layer is a continuous layer covering all the surfaces of the first element.
7. A support element as claimed in claim 6, in which the first element is coated with the second element.
8. A support element as claimed in any preceding claim, in which the first element is provided with an external surface which is adapted to engage a brace engaging component in use, and an internal surface which contacts the second element.
9. A support element as claimed in any one of claims 4 to 7, in which the first element comprises a plurality of surfaces, and in which all of the surfaces are internal surfaces which contact the second element.
10. A support element as claimed in any preceding claim, in which the first material comprises polyurethane.
11. A support element as claimed in claim 10, in which the first material is a polyurethane in rigid foam form.
12. A support element as claimed in any preceding claim, in which the first material has a density of 100 to 750 kg.m3.
13. A support element as claimed in any preceding claim, in which the first element has a thickness of 2 to 20 cm.
14. A support element as claimed in any preceding claim, in which the second element is provided with an external surface which is adapted to engage the ground, in use, and an internal surface which contacts the first, element.C
15. A support element as claimed in claim 14, in which the second element provides all C the external surfaces which contact the environment of the support element. Co
16. A support element as claimed in any preceding claim, in which the second material is of polyurethane.
17. A support element as claimed in claim 16, in which the second material is of polyurethane in non-foam form.
18. A support element as claimed in any preceding claim, in which the second material has a density of 800 to 1750 kg.m3.
19. A support element as claimed in claim 2, or any one of claims 3 to 18 when dependent on claim 2, in which the second element has a thickness of 0.2 to 5 cm.
20. A support element as claimed in claim 4, or any one of claims 5 to 18 when dependent on claim 4, in which the second element has a thickness of 0.1 to 1 cm.
21. A support element as claimed in any preceding claim, in which the support element has a weight of less than 70% the weight of a slab of equivalent volume made of polyurethane in non-foam form.
22. A support element as claimed in any preceding claim, in which the support element has a weight of less than 50% the weight of a slab of equivalent volume made of polyurethane in non-foam form.
23. A support element as claimed in any preceding claim, in which the first element is bonded to the second element.
24. A support element as claimed in claim 23, in which the bond is formed by one or C more parts of the second element entering one or more recesses in the first element.

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25. A support element as claimed in any preceding claim, in which the support element is CO provided with one or more handles.
26. A method of bracing equipment, the method comprising: providing a support element between a component of the equipment and the ground; bringing the component into contact with the support element, the support element being in contact with the ground, the support element being formed from a first element of a first material and a second element of a second, different, material.
27. A method as claimed in claim 26, in which the method includes providing at least two support elements, each being provided between a separate component of the equipment and the ground.
28. A method as claimed in claim 26, in which the method further includes, for each support element, bringing the component into contact with the support element, the support element being in contact with the ground.
29. A method as claimed in claim any one of claims 26 to 28, in which the method includes varying the centre of gravity of the equipment, once the equipment is braced.
30. A method as claimed in any one of claims 26 to 29, in which the support element is a support element as claimed in any one of claims 2 to 25.
31. A kit comprising: equipment, the equipment having a centre of gravity which is variable, and one or more bracing components; and one or more support elements, one or more of the support elements being formed Q from a first element of a first material and a second element of a second, different, material.Q

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32. A kit as claimed in claim 31, in which the one or more support elements take the form of a support element as claimed in any one of claims 2 to 25.
33. A kit as claimed in either of claims 31 or 32, in which the kit includes at least one support element for each bracing component provided on the equipment.
34. A kit as claimed in any one of claims 31 to 33, in which the kit includes two or more support elements.
35. A kit as claimed in any one of claims 31 to 34, in which the equipment is a crane.
36. A kit as claimed in any one of claims 31 to 35, in which the equipment has an extendable component, which can be extended by changing its length and/or by changing its elevation.
37. A kit as claimed in any one of claims 31 to 36, in which the equipment is provided with two or more bracing components, one or more of the bracing components having a first, stowed position and a second, deployed position.
38. A kit as claimed in any one of claims 31 to 37, in which one or more of the support elements is provided between a brace component and the ground, the brace component engaging the upper surface of the support element. 0)CC Co CsJ