PIPEWORK INSERT DEVICE The invention is concerned with insert devices suitable for use in the construction and/or maintenance of an arrangement of pipes involving the provision of a fluid path through a series of pipe lengths.

In for example the construction of a network of pipes in a chemical engineering plant, a problem which frequently arises is to provide, say, a valve, either a flow control valve or a relief valve, in a pipeline so as to be positioned between the adjacent ends of two lengths of pipe, that is, intervening between two pipe portions. It may frequently happen that in the construction of a pipeline, the required valve or flow meter to be inserted is not immediately available. Delay therefore arises, whether of hours or days, before the pipeline can be continued beyond the site of the valve with any certainty that when the valve is eventually inserted in position, the gap left for it will prove to be dimensioned to receive it accurately.

Attempts to overcome this problem may be made by fabricating insert spacers or the like of the desired dimensions. These may be found time consuming to produce and it is difficult to ensure a high level of accuracy where the two adjacent pipe portions are arranged, say, at right angles to one another.

Another situation in which problems may arise is in the case where it is necessary to remove a valve or flow

meter for re-calibration, adjustment or replacement, where it may be undesirable to leave a gap even for a short time since movement may occur which may alter the distance across the gap and prevent accurate re-insertion.

It is an object of the present invention to provide means to avoid or mitigate one or more of the above disadvantages according to the circumstances.

Moreover, where a fault occurs it is sometimes not clear whether a leakage is present in the valve or the pipe. When the valve is removed for repair, the pipeline itself, even when an insert spacer is used, cannot be pressure-tested.

The invention provides, in one of its several features, an insert device for use in the construction and/or maintenance of an arrangement of pipes, comprising a body portion having at least two recesses each adapted adjustably to receive an elongate member extending therefrom, each of said elongate members including a head portion extending radially of the elongate member, at an outer free end portion thereof, said head portion being apertured to receive fastening members and adapted to be secured to open ends of pipe portions.

Preferably, the recesses are internally screw threaded to receive said elongate members in the form of threaded rods. Alternatively, particularly in non-heavy duty situations, the elongate members may comprise portions capable of telescopic movement with respect to the body

portion.

Advantageously, an outwardly facing surface of each head portion is provided with a reference point co-axial with a longitudinal axis of the associated elongate member.

Conveniently, the head portions may be provided with at least two elongate apertures to provide tolerances for alignment with bolt-receiving bores in an abutment flange of the pipe portion.

Alternatively, the head portions may be in the form of a circular disc or plate member provided with a series of apertures in a circular array and adapted to align with bolts received in an abutment flange of the pipe portion.

Advantageously, each said circular disc or plate member may be provided with a nipple adapted to receive, when uncapped, a pressure-measuring device or manometer, or alternatively, a bypass passage in the form of a tube. It will be appreciated that the use of a bypass tube will permit the pipe to remain in service during the time the valve is removed, if desired. Alternatively, it enables a pipe to be pressure-tested in the absence of the valve.

In another example of the use of a bypass passage, an insert device as described in the fifth paragraph of the present specification may be provided head portions which comprise annular disc or plate members provided with a series of apertures in a circular array and adapted to align with bolts received in an abutment flange of a pipe portion, in which said elongate members comprise hollow

tubular rods and in which each of said recesses are in communication with the or each other recess to form a passage through the body portion and the elongate members, sealing means being provided to ensure a fluid-tight fit between the elongate members and the passage-forming recesses of the body portion.

Conveniently, the hollow tubular elongate members may be initially slidably received in the passage-forming recesses, 'lip portions of the recesses being adapted to be clamped by an annular sealing device, for example a metal olive, including a securing nut.

There will now be described several examples of devices according to the invention. It will be understood that the description, which is intended to be read with reference to the drawings, is given by way of example only and not by way of limitation.

In the drawings:

Fig. 1 is a perspective view of a first device according to the invention;

Figs. 2,3,4,5 and 6 are perspective views of a second, third, fourth, fifth and sixth device respectively;

Fig. 7 shows two pipe portions having open ends to be bridged by the first device of Fig. 1;

Fig. 8 shows the first device in the course of use;

Figs. 9-13 show various ways of mounting pipes and devices according to the invention; and

Figure 14 shows a longitudinal section through a

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seventh device according to the invention.

The first device, shown in Fig. 1, comprises a body portion 2 having a generally L-shaped side view, end portions of the body portion being provided with recesses 4 which are screw-threaded to receive elongate members in the form of threaded rods 6. Mounted on each rod is a lock nut 8.

Each rod 6 is provided with a fixed head portion 10 comprising a cross member provided with elongate slots 12. On an outwardly facing surface of each head portion 10 is a centrally disposed reference point 14 arranged co-axially with a longitudinal axis of the associated rod 6. The purpose of the reference point will be explained below.

Fig. 2 shows a second, device similar to that of Fig. 1, but differing in that the second device comprises a body portion 16 which is adapted to accept a third rod 6 with its associated head portion 10. An alternative form of body portion 18 having a generally T-shaped configuration is shown in Fig. 3.

The head portions 10 of the devices shown in Figs. 1 - 3 are elongate in shape and adapted to span the open mouth of a pipe portion 20, shown in Fig. 2 in dotted line. Bolts 22 secure a flange 24 to the pipe portion 20 with respect to the head portion 10, passing through the slots 12. It will be appreciated that because the slots are elongated, a range of diameters of pipe 20 may be

accommodated.

Fig. 4 shows a fourth device similar in many respect to that of Fig. 1, with the exception that one of the rods 6 has a head portion 26 comprising a disc-like plate provided with bores 28 corresponding in layout with the bolt receiving apertures in a pipe portion flange. The plate 26 may therefore be used as an end cap for a pipe portion, to blank off the mouth thereof. A nipple 30 is provided to receive a pressure testing or monitoring device (not shown) as required, the nipple having a cap 32 when not in use.

Fig. 5 shows an arrangement in which a fifth device is provided with a linear body portion 34 having two opposite rods 6 extending therefrom, each having a disc-like plate 26 as its head portion. Nipples 30' of the two plates are linked by a flexible pipe 36 which, in use, enables the full lengtlϊ of pipework to be checked for leaks even though an intervening valve is absent and a device according to the invention is inserted.

Such a linear body portion 34 may of course also be used with head portions 10' (Fig. 6), which are similar to the head portions 10 shown in Figs. 1 - 3. With each type of head portion, an intervening gasket may be used if required, e.g. for blanking off the partially open pipe end.

Fig. 7 shows a typical situation in which the present invention finds particular use. In the construction of a

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pipe network a pipe section 38 is placed in position leading to a bend in the path of the pipework at which a valve (not shown) is to be inserted. A second length of pipe section 40 is to be connected to the valve so as to continue the fluid.

However, the valve may not be available for some reason. In conventional procedures, substitute spacer devices may be fabricated to simulate the dimensions of the valve. Where as in the present instance, an angled bend needs to be taken into consideration, it is not easy accurately to make such a fabricated spacer nor to attach it to a flange 42 of the pipe 38 in such a way that the second pipe 40 can be accurately positioned with respect to the absent valve. Inaccuracies almost inevitably arise and when attempts are made to position the valve itself in due in place of the spacer, the gap is found to be wrongly dimensioned.

Two dimensions a and b are critical in the situation illustrated in Fig. 7. Dimension a is taken between the centre line of pipe portion 40 and the contact face of the flange 42. Dimension b is taken between the centre line of pipe portion 38 and the contact face of a flange 44 of the pipe 40. If these two dimensions are accurately taken from the technical specification data of the valve and reproduced in the manner explained below, the valve will fit exactly.

The operator will therefore take a first device of the

kind shown in Fig. 1 and will rotate the head portion 10a, see Fig. 8, until the distance between the centre line of head portion 10b, identified visually by the reference point 14, and the plane of the outer face of head portion 10a is exactly as dimension a. The lock nut 8 is screwed tight and the operator then rotates the head portion 10b which moves outwardly of the body portion 2 (arrow A) until the distance between the centre line of head portion 10a (reference point 14) and the plane of the outer face of the head portion 10b is exactly as dimension b. The second lock nut is then tightened.

The device is secured to the pipe portion 38 by means of two bolts 46 and the second pipe portion 40 may then be secured in a similar manner to the head portion 10b. Construction of the pipework may then continue. When the valve is available, the device may be removed and the valve will be found to fit accurately in place.

It will be observed that the examples illustrated in Figs. 1 to 6 are all free-standing in the sense that they are supported by the pipework in which they are inserted. In some circumstances it may be preferable to support the inserts by -attachment to floors, walls or joists.

Fig. 9 shows a floor mountable support bracket 48 adapted to engage a device similar to that shown in Fig. 6. The bracket 48 has a clamp 49 and a screw-threaded insert 50 hich permit accurate heightwise adjustment. This type of bracket may also be used to support the

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pipework itself as shown in Figs. 10a and 10b.

Alternatively, an expandible T-shaped support 52 such as is shown in Fig. 11 may be used to span a space between joists or to engage with the I-shaped flanges thereof by means of right-angle brackets 54 (Fig. 12) , a clamp 56 extending from the support adapted to engage a body portion such as portion 34 of Fig. 6. The T-shaped support 52 may be vertically or horizontally (Fig. 13) orientated.

The seventh device, shown in Fig. 14, comprises a body portion 60 in the form of a length of heavy duty hollow pipe having an internal thread 62. Lip portions 64 of the pipe body portion 60 are provided with an external thread 66 and an inturned flange 68 having a frusto-conical surface 70.

A hollow elongate member 72 is received in each of the two end portions of the pipe body portion 60. Inner end portions of each member are provided with an annular member 74 which has an external thread engaging the thread 62 so as to permit adjustment of the distance by which the member 72 extends from the body portion 60. At the opposite end of each member 72 is a head portion 76 in the form of an annular pipe flange, sealingly secured at 78 to the member 72 to provide passage for fluid.

Slidingly mounted on the member 72 are two brass olives 80, each adapted to abut the lip portions 64 of the body portion 60. A securing nut 82 clamps each olive

firmly against the member 72 and the surface 70 of the lip portions 64.

The device may therefore be introduced between open pipe ends to replace a valve-containing section as before. During the time the device is in place the main pipework may be returned to normal use to carry liquid therethrough. If desired, a stop-valve, or alternatively a pressure-measuring device, may be provided at a location 84 indicated by chain-dot lines at an intermediate zone of the body portion 60.

Various modifications may be made within the scope of the invention as defined by the following claims.