AU2012201885A1 - A pipe lift attachment - Google Patents

Abstract

A vacuum pipe lift attachment (11) adapted to be mounted to a boom 5 member for remote connection to a vacuum source, the attachment having; a vacuum plate (17) with a lower vacuum surface, a connector (20) having a lower end pivotally mounted to the vacuum plate about a horizontal pivot point (22) and an upper end adapted to be mounted to a hydraulic rotator (15). ()

Description

1 A PIPE LIFT ATTACHMENT FIELD OF THE INVENTION 5 The present invention relates to a pipe lift attachment of the type mountable to a work machine for lifting and manoeuvring pipes. In particular the present invention relates to a pipe lift attachment for lifting and manoeuvring plastic pipes having a diameter between about 100mm to about 1000mm. 10 BACKGROUND OF THE INVENTION Large diameter plastic pipes are used in the mining, oil and, utilities and gas industries. Advantages of plastic pipe over conventional steel and concrete pipes include chemical resistance and in particular corrosion resistance, flexibility and weight allowing ease of installation and reduced labour and transport costs and 15 hydraulic flow characteristics. Smaller diameter pipes of less than about 100mm are available in coils of up to about 300 meters. Larger diameters are provided in lengths, typically between 12m and 15m. A particularly preferred pipe is formed from polyethylene (PE). 20 The present invention will be described with particular reference to a device for lifting and manoeuvring a length of PE pipe during pipe laying operations and in particular in relation to butt welding operations. However, it will be appreciated that this is by way of example only and no limitation is intended thereby. The pipe lift attachment of the present invention may be used to lift any suitable length 25 arcuate object. In the present specification, the term large diameter pipe refers to pipe having a diameter between about 100mm to about 1000mm that is supplied for laying in lengths of pipe rather than a coil. 30 2 During a pipe laying operation, such as a gas pipe, lengths of pipe are first laid out in a string. The lengths are then joined using butt fusion or welding machines. The machines have two sets of circular pipe clamps mounted to a frame. A first set of clamps is stationary with respect to the frame and clamps the end of a 5 joined length of pipe. The second set of clamps is moveable with respect to the frame and are generally operated hydraulically. The second set of clamps receives the end of a pipe to be joined to the growing pipe line. When the respective ends of the pipe are loaded onto and clamped on the 10 machine, an electrically heated twin sided heating plate is placed between the two ends so as to heat the ends of the pipe. The plate is removed and the moveable second set of clamps move the second pipe inwards such that the two heated ends meet and are fused together. The circular pipe clamps are opened and the joined pipe is unloaded from the machine and placed in a trench or alternatively 15 on an above ground installation. It will be appreciated that during such pipe laying operations, pipes must be handled a number of times, first being lifted from transport and placed on the ground, loading and unloading of the butt welding machine and final placement. 20 Lengths of pipe may be lifted using a range of power lifting equipment such as forklifts, cherry pickers, dedicated pipe lifting machines, backhoes, front end loaders, cranes and excavators. Fabric slings are recommended for lifting and handling PE pipe so as to prevent damage to the pipe surface. Wide band slings are used to distribute the lifting load over a large area and may be used with 25 spreader bars. Chains, steel cables, wire ropes and hooks must not be used directly on PE pipes. Vacuum lifting devices that are mountable to a boom of heavy machinery such as an excavator, crane and the like are also used in the pipe laying industry for lifting 30 heavy concrete and steel pipes in the order of 8 000kg and above. They may also be used for lifting very heavy plastic pipe of over 1 m diameter. These vacuum lifting devices are self-contained and have a diesel operated vacuum pump with 3 an upper end adapted to be mounted to an hydraulic arm and a lower vacuum shoe or suction pad. Vacuum lifting devices have not been used to lift and manoeuvre plastic pipe of 5 diameters up to about 1000mm and in particular within the range of about 250 to about 550mm. First, it is considered impractical as the weight of the pipe lifter with its' diesel engine can approach that of the pipe to be lifted. In other words a significant part of the lifting power of the machine is being used to lift the vacuum lift device itself. This is not only inefficient but may require a heavier machine than 10 would normally be required. It will be appreciated that such inefficiencies and the use of a larger, more expensive machine may add to costs. Still further the manoeuvring ability of the self-contained vacuum devices are considered too limiting for use with the degree of accuracy required to load and unload a butt welding machine. 15 It is therefore an object of the invention to provide an alternate lifting device for lifting large diameter plastic pipe. SUMMARY OF THE INVENTION 20 According to a first broad form of the invention, there is provided a vacuum pipe lift attachment adapted to be mounted to a boom member for remote connection to a vacuum source, the attachment having; a vacuum plate with a lower vacuum surface, a connector having a lower end pivotally mounted to the vacuum plate 25 about a horizontal pivot point and an upper end that is adapted to be mounted to a hydraulic rotator. A boom member refers to any hydraulically operated arm, stick or other member capable of lifting the pipe lift attachment and associated load. The boom member 4 may be part of or an attachment to a work machine such as a crane, excavator, backhoe, pipe-laying machine or the like. A hydraulic rotator is well known in the art and is a hydraulically operative coupling 5 mounted to the end of a boom member that is capable of rotating a coupled work attachment. The pipe lift attachment is adapted for remote connection to a vacuum source. Typically, where the boom member is mounted to a work machine, the vacuum 10 source is a vacuum pump mounted on the body of the work machine. Preferably, the remote vacuum pump is a hydraulic power pack in which the hydraulic circuit is fluidly connected to the hydraulic circuit of the work machine. An advantage of such an arrangement is ease of use in that the vacuum pump is engaged when the work machine is turned on. 15 A further advantage of a hydraulic power pack over a mechanically operated pump such as a diesel motor is that liquid fuel operated motors are subject to a large amount of vibration. When the motor is mounted to the end of a boom member as per conventional pipe lift machines the vibrational energy is 20 transferred to the various attachment points that are free to move. On the other hand, when fixedly mounted to the body of a work machine, there is nowhere for the vibrational energy to be transferred. The present inventor has observed that this vibrational energy has an adverse effect on the operation of the motor as it loosens parts and/or creates accelerated wear. 25 A preferred vacuum pump arrangement is that which is formed from a modular construction in that the power pack and vacuum tank are provided as separate units operatively connected together. An advantage of this arrangement is that it allows various mounting of the respective modules. The modules can be mounted 30 together or separately on the body of the work machine.

5 In an alternative embodiment of the invention, there is provided a work machine having a body and a hydraulically operated boom member, a vacuum pipe lift attachment mountable to the boom member, a vacuum source mounted to the body remote from the boom arm for vacuum connection with the vacuum pipe lift 5 attachment, wherein the vacuum source is a hydraulically operated vacuum pump. The vacuum plate has a lower vacuum surface. Suitably the vacuum surface is complimentary to the shape of a load to be lifted. In the case of lifting pipes the lower surface is suitably acuate. 10 The vacuum plate can pivot about the horizontal pivot point. The pivot point is located within the pipe lift attachment itself which is below the lowermost portion of the rotator. This allows for easier manoeuvrability and the ability for the butt weld machine operator to guide a pipe end onto a butt welding machine. 15 Typically, the range of pivotal motion is limited by stops, preferably resilient stops that provide a cushioning stop. The range of movement is typically between 152 to 200 on either side of the horizontal plane. 20 Typically, the upper end of the connector is fixed to a connecting plate adapted to be bolted to the lower end of a hydraulic rotator. As discussed above, the vacuum source is remote from the vacuum plate such that a vacuum line connects the source and the vacuum shoe. Preferably, the 25 vacuum line passes through the interior of the hydraulic rotator. In this way, the rotator is able to rotate through a full 3600 without being caught up by external vacuum hoses. According to a further broad form of the invention, there is provided a vacuum 30 pipe lift assembly comprising a vacuum pipe lift attachment having; 6 a vacuum plate with a lower vacuum surface, a connector having a lower end pivotally mounted to the vacuum plate about a horizontal pivot point and a hydraulic rotator mounted to the upper end of the connector, wherein the vacuum lift attachment is adapted for remote 5 connection to a vacuum source. According to a still further broad form of the invention, there is provided a work machine having a boom arm with the vacuum pipe lift assembly of the previous embodiment mounted to the boom arm and a hydraulic vacuum pump in vacuum 10 communication with the vacuum shoe, the vacuum pump being mounted on the work machine body at a location remote from the vacuum pipe lift assembly. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a perspective view of a preferred pipe lift attachment of the 15 present invention; Figure 2 is a schematic view of a preferred vacuum source for use with the pipe lift attachment as shown in Figure 1; Figure 3 shows the vacuum source as show in Figure 2 with power pack module in the open configuration; and 20 Figure 4 shows the pipe lift attachment as shown in Figure 1 and the vacuum source shown in Figures 2 and 3 mounted to a work machine and in use lifting a pipe. DETAILED DESCRIPTION OF THE DRAWINGS 25 Figure 1 shows a preferred pipe lift attachment 11 of the present invention. The pipe lift attachment has a vacuum shoe 17 with a curved lower surface complimentary to a pipe to be lifted. At each end of the shoe 17 are rubber guides 18 for guiding the shoe The attachment includes a vacuum gauge 10. A 7 connector 20 is pivotally mounted to the shoe 17 about pivot point 21. The upper end of the connector 20 is rigidly mounted to a circular connecting plate 22 which in turn is bolted to the lower end of the hydraulic rotator 15. The hydraulic rotator is in 15 is mounted to a quick hitch adapted for attachment to a stick of an 5 excavator. Rubber stops 23 limit and cushion pivotal movement to within about 102 to 200 about the horizontal plane. The upper ends of stops 23 contact the lower surface of plate 22 so as to restrict movement. The pipe lift device 11 has a vacuum hose 25 extending from an air outlet 26 on 10 the upper side of the vacuum shoe 17 and which passes through the interior of the hydraulic rotator 15 and out through the top of the rotator 15 to a second vacuum hose 27 (shown in figure 4). that is in vacuum communication with the vacuum source 30 (also shown in Figure 4). The connector 20 has an aperture This arrangement enables the pipe lift attachment 11 and attached pipe 16 to be 15 rotated though a full 360 without entanglement of vacuum hoses. The second vacuum hose 27 is connected to a hydraulic vacuum pump 30 mounted to the body of the excavator Figure 2 shows a preferred vacuum source 30. The vacuum source is in modular 20 form with a vacuum power pack module 31 and a vacuum tank module 32. The tow modules are shown as mounted together, however, they can be mounted on the body of a work machine remotely, depending upon the external configuration of the work machine body. The power pack 31 has a cover 33 that can be open and closed to allow aces to the hydraulic motor for servicing and the like. 25 Figure 3 shows the vacuum source 30 in which the cover of the power pack is in the open position. Figure 4 shows the pipe lift attachment 11 and vacuum source 30 mounted to a 30 work machine that is an excavator 40. The excavator has a body 41, boom arm 8 42, stick, 43. The pipe lift attachment 11 is mounted to the stick 43 by means of the hydraulic rotator 15 and quick hitch 14. A pipe 16 is shown as being lifted by the excavator 40 via the pipe lift attachment. 5 It may be seen that the pipe has a degree of sag. As the pipe is lowered to a ground surface the ends will reach the surface first. The ability of the pipe lift attachment to pivot can accommodate this degree of sag. This may allow more accurate placement of the pipe and/or reduce the risk of pipe damage. 10 The pipe lift attachment can also lift a pipe at one end and can transmit the required thrust to move the end of the pipe into a desired position for butt welding or the like. The ability of the pipe lift attachment to pivot in response to the trailing lone end of the pipe may assist an operator in positioning the pipe in a butt welding machine. 15 Conventional methods of lifting sections of pipe during welding or fusion operations use a sling. This requires an operator to tie and untie the sling around the pipe. This conventional procedure for field welding a PE pipe requires 3 operators. A first operator to operate the excavator, a second operator to control 20 the butt welding machine and a third operator to tie and untie the sling. However, using the device of the present invention, engaging, lifting and releasing the pipe may be conducted by the excavator operator, thereby avoiding the requirement for a sling operator. This has advantages in terms of labour costs and safety. 25 Still further, location of the pivot point allows an operator to easily tilt and/or control the tilt of a pipe. It would be appreciated that if the pivot point was located above the hydraulic rotator the additional weight of the rotator and location of the pivot point above head height would make manoeuvring not only more difficult but more dangerous to an operator. 30 9 It will be appreciated that various modification and changes may be made to the invention as described and claimed herein without departing from the spirit and scope thereof.

Claims (13)

1. A vacuum pipe lift attachment adapted to be mounted to a boom member 5 for remote connection to a vacuum source, the attachment having; a vacuum plate with a lower vacuum surface, a connector having a lower end pivotally mounted to the vacuum plate about a horizontal pivot point and an upper end adapted to be mounted to a hydraulic rotator. 10

2. The attachment of claim 1, wherein the upper end of the connector has a circular plate adapted to be bolted to the lower end of a hydraulic rotator.

3. The attachment of claim 1 for claim 2 further including stops for limiting pivotal moment

4. The attachment of claim 3, wherein the stops limit moment to about 10* to 15 about 200 about the horizontal plane.

5. The attachment of claim 3 or claim 4, wherein the stops are formed from a resilient material.

6. The attachment of any one of claims 1 to 5, further including pipe guides located at each end of the vacuum plate. 20

7. According to a further broad form of the invention, there is provided a vacuum pipe lift assembly comprising a vacuum pipe lift attachment having; a vacuum plate with a lower vacuum surface, a connector having a lower end pivotally mounted to the vacuum plate about a horizontal pivot point and a hydraulic rotator mounted to the 25 upper end of the connector and the vacuum lift attachment is adapted for remote connection to a vacuum source. 11

8. The assembly of claim 7 including a vacuum line that passes from the vacuum shoe through the centre of the hydraulic rotator to connect with a vacuum hose at the upper end of the hydraulic rotator. 5

9. A work machine having a hydraulic boom arm with the vacuum pipe lift assembly of claim 7 or claim 8 mounted to the boom arm and a hydraulic vacuum pump in vacuum communication with the vacuum shoe, the vacuum pump being mounted on the work machine body at a location remote from the vacuum pipe lift assembly.

10 10. The work machine of claim 9, wherein the vacuum pump is hydraulic and is fluidly connected to the hydraulic fluid reservoir of the work machine.A work machine having a body and a hydraulically operated boom member, a vacuum pipe lift attachment mountable to the boom member, a vacuum source mounted to the body remote from the boom arm for vacuum 15 connection with the vacuum pipe lift attachment, wherein the vacuum source is a hydraulically operated vacuum pump.

11. The work machine of claim 10 or claim 11, wherein the hydraulic vacuum pump has a power pack module and a vacuum tank module.

12. A pipe lift attachment, substantially as hereinbefore defined with reference 20 to Figure 1.

13. A work machine for lifting pipes, substantially as hereinbefore described with reference to Figure 4.