GB2502537A - Excavator attachment for pipe fracturing - Google Patents

Abstract

An excavator attachment 1 for fracturing a pipe includes a main body section 20 in the form of a hook 22, a hydraulic ram (42, fig 3) with a pipe engaging portion 30. The ram moves the pipe engaging portion into contact with the pipe allowing fracturing when pressure is increased. The pipe engaging portion is preferably a plate having a curved profile with a projection 34 in the centre. The device may consist of two parallel plates (fig 3,4) making up the hook section and the pipe engaging section may also comprise two parallel plates. The device is preferably arranged to be attached to a standard quick coupler and includes hydraulic couplings to connect with the hydraulics of the excavator.

Description

Improvements in and relating to pipe breaking The present invention relates to fracturing pipes in-situ, in situations where the existing pipe is intended to serve as a conduit for a replacement pipe. Underground pipes are in place which carry water or gas to premises, or effluent away from premises for treatment or disposal.

Many such pipes have been in place for many years, and their useful life is drawing to a close, meaning that replacements are needed.

The upheaval created by digging up lengthy stretches of road, in order to lay new pipe is considerable and, in recent times, better, cheaper and more convenient solutions to the problem of installing new pipe have been sought.

One such solution involves running new pipe, formed from plastics material such as HDPE / MDPE Polyethylene, inside the existing pipe, which is often formed from cast or spun iron. Prior art techniques for installing the new pipe involve digging a pit surrounding a section of the pipe at intervals along the length of the pipe e.g. every 100 metres. The exposed section of the pipe is fractured to create an access to the interior of the pipe. The replacement plastics material pipe is then introduced to run inside the existing pipe which merely serves as a conduit to receive the new pipe. The new pipe is then either pushed through the existing pipe, using suitable pushing apparatus or is pulled along from the next access point using a winch.

A problem with prior art arrangements is that once the buried existing pipe is exposed, it must be broken or fractured to allow access to its interior. Since the exposed pipe is located at the bottom of an excavated pit, usually at least a metre deep, it is not generally practicable to use machinery to perform this task, so the usual method employs labourers using sledge hammers, breaking bars or elongate metal rods to repeatedly strike the exposed pipe.

However, it is not uncommon for injuries to result from this process and it is considered an unsafe way to break the pipe. However, there is no viable alternative in most circumstances.

There therefore exists a need to address such problems in the prior art, and other problem not specifically mentioned herein.

According to the present invention there is provided an apparatus and method as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.

For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which: Figure 1 shows a side view of a first embodiment of the present invention; Figure 2 shows a side view of a second embodiment of the present invention; Figure 3 shows a detailed view of a part of the second embodiment of the present invention; and Figure 4 shows a detailed view of another part of the second embodiment of the present invention.

Figure 1 shows a side view of a pipe-breaking apparatus 1 according to a first embodiment of the present invention. The apparatus 1 is arranged to be fitted to an excavator, at the end of an elongate arm where a bucket or other apparatus is usually disposed. The apparatus 1 is connected to the hydraulic system of the excavator using standard quick release couplings 44 The apparatus 1 comprises attachment means 10, which allow the apparatus to be connected to the excavator arm via two excavator standard quick release hydraulic couplers.

The main body of the apparatus I comprises a pair of relatively elongate sections 20, at the lower end of each is disposed a hook portion 22. The elongate sections 20 and hook portion 22 are each integrally formed from a single sheet of EN 161 steel, as is all of the material used for the apparatus.

As can be seen in Figures 2-4, the pair of elongate sections are joined together at several points by spacer bars 24 to form a frame structure in which is disposed a hydraulic ram 40. The upper end of the cylinder of the ram 40 is coupled to the elongate sections 2. The piston 42 which extends from the cylinder 40 is terminated in a pipe-engaging portion 30 which, in use, contacts the exposed upper surface of the pipe to be fractured.

The pipe-engaging portion 30, in the embodiments shown, comprises a pair of plates, in a spaced relationship, positioned at the end of the piston 42. Two single plates are used here as it is easier to mount onto the hydraulic ram. Each plate is essentially arcuate in shape, having a projection 32 at each extreme edge of the plate. At the approximate centre of each plate is a further projection 34. The purpose of the arcuate shape is to ensure that the plate conforms approximately to the outer profile of the pipe, and the two projections 32 help to secure the pipe in the aperture once the fracturing process is underway. The purpose of the central projection 34 is to concentrate pressure at a certain point of the pipe to aid the fracturing process.

The embodiment shown in Figure 1 has a hook portion which is essentially linear and is arranged to be essentially parallel to the ground, in use. The aperture 26, created between the main elongate section 20 and the hook 22 is arranged to accommodate a section of the pipe to be broken. In order to locate the pipe in this aperture, a small section of ground beneath the pipe is excavated so that the hook 22 can be positioned beneath the pipe and the pipe therefore sits within the aperture 26.

The embodiment shown in Figures 2-4 has a slightly different arrangement in that the hook 22 has a more curved profile, which may assist in positioning it beneath the pipe.

Otherwise, the two embodiments of the figures operate in an identical fashion.

Once the apparatus has been positioned so that the pipe sits in the aperture 26, the pipe fracturing process can commence. It is important to note that while this process is occurring, no personnel are required to be in close proximity to the pipe and all control is performed from the cab of the excavator to which the apparatus 1 is coupled. This ensures that no personnel are placed at risk during the fracturing operation.

To commence the process, hydraulic pressure is applied to the ram 40. This causes the piston 42 to extend from the cylinder and so move the pipe engaging portion 30 towards the exposed upper surface of the pipe to be fractured. The central projection 34 contacts the pipe and with increased pressure, the pipe is fractured. Since the pipe is formed from cast / spun iron which is brittle, it tends to fracture completely, rather than deform under pressure as other materials might.

Once the pipe has fractured, the apparatus 1 may be simply removed from the pit, under control of the operator of the excavator.

Since access to the pipe is now possible, the next stage of installing the new pipe can begin in whichever way is selected.

The fracturing operation is repeated at intervals along the length of the original pipe so that new pipe can be pushed or pulled, as necessary, into the conduit formed from the original pipe. It may be necessary to excavate smaller pits along the length of the pipe, and to fracture the pipe so revealed, in between the pits require for feeding the new pipe into the conduit formed from the old pipe. This is so that service access may be provided to individual properties. For instance, pits at approximately 100 metre intervals may be required in order to feed new mains pipe into the conduit formed from the original pipe, but access must be provided adjacent each property so that the property can be connected to the new mains pipe.

This means that the original pipe must be fractured where the new service pipe to the property is to join to the mains pipe.

Embodiments of the present invention therefore allow for a quicker, safer and more convenient method of fracturing, in-situ, a pipe in which a replacement pipe is to be installed.

Embodiments are able to couple easily with existing site equipment which is on-site anyway already, minimising the need to provide further specialist equipment.

Since no site personnel are required to be in close proximity to the site while it is being fractured, pipe installation using an embodiment of the present invention is considerably safer

than manual prior art methods.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims (7)

1. CLAIMS1. Apparatus for fracturing a pipe, comprising: attachment means to attach the apparatus to an arm of an excavator; hydraulic coupling means to couple to a hydraulic system of the excavator; a main body section, having a hook portion to engage with an underside of the pipe to be fractured; a hydraulic ram comprising a pipe-engaging portion, arranged such that the pipe-engaging portion is movable to engage with the pipe.
2. 2. The apparatus of claim 1 wherein the main body section comprises a pair of substantially parallel plates in a spaced relationship, wherein the hydraulic ram is disposed between the plates.
3. 3. The apparatus as claimed in any preceding claim wherein the pipe engaging portion comprises a plate having a substantially curved profile to substantially conform to an outer profile of the pipe.
4. 4. The apparatus as claimed in claim 3 wherein the plate comprises a projection positioned substantially at its centre to contact the pipe.
5. 5. The apparatus as claimed in claim 3 or 4 wherein the pipe engaging portion comprises two such plates arranged in a spaced relationship.
6. 6. The apparatus as claimed in any preceding claim wherein the hook portion has a curved lower section so as to substantially conform to an outer profile of the pipe.
7. 7. Apparatus substantially as herein described and having particular reference to the accompanying drawings.