FI75416B - REFERRALS ARE REFERRED TO INSULATION SPECIFIC IN OIL-ELLER GASLEDNING. - Google Patents

Description

1 75416

The present invention relates to a method for insulating oil and gas pipelines on the construction site, which are built on ground-based structures at certain intervals in the terrain, the line being arranged on support structures and secured thereto, preferably by means of hoops extending around the line and Insulating elements consisting of a metal protective sheath and an insulator attached thereto, which can be closed around the wire to be insulated, are used for insulation, whereby the elements between the support structures are installed in succession with glued seams.

Today, liquids and gases have to be transported 15 more and more long distances in difficult terrain conditions by means of pipelines with a diameter of 500-2000 mm. Terrestrial pipelines often require thermal insulation. This is especially the case if the pipeline is built in an area with unfavorable weather conditions for relocation.

20 Pipelines are now primarily insulated manually at the installation site. Separate factory-made parts of the insulation gutters are transported on site, which are placed by hand around the pipe. The gutters are then covered with sheet metal sheaths. At the cable support points, the insulation work is performed as a tailor-made work according to the shape of the support structure required by the conditions. The movement of the shield due to temperature differences is usually compensated by separate leveling devices installed manually.

There is little mechanized insulation work. En-30 is the first and reportedly the only large-scale company in this sense to be the insulation of the oil pipeline through Alaska. The inner diameter of the pipe is about 1200 mm and it runs in arctic terrain. Factory-made full-size insulation elements have been used there, which, when installed, thus extend around the entire pipe. The dimensions of the elements are 7 x 4.6 m and they consist of thermal insulation glued to the tin protective * _ / 2 7541 6 jacket. The elements were delivered to the installation site in planar form and, due to their large size, were transported on special equipment once folded. At the construction site, the elements were folded open with a special machine. After the opening 5, they were transferred by means of a separate mobile lifting crane and a mounting device suspended thereon onto the pipeline around which they were pressed by said hydraulically operated mounting device.

However, in said Alaskan oil pipeline, mechanical insulation work was carried out only on the straight pipe section between the support structures. In the case of support structures and curves, the installation was carried out manually. The pipes and the immediate fasteners are covered with molded parts made of polyurethane, the surface of which is reinforced with a layer of fiberglass / 15 polyester. Separate special joints have been developed for these elements. The movement of the insulation elements due to temperature fluctuations was compensated by hand-mounted compensating beams there as well.

The methods known today can be summarized as having the following disadvantages:

The insulation solution of the support points is not suitable for mechanical installation, and no suitable installation device can be found for this installation work.

The fulcrum insulation is always placed symmetrically with respect to the centerline of the tu-25 point. Since the distance between the support points cannot be precisely determined in advance due to the terrain, it is necessary to use fitting pieces or shorten the last element.

The insulating elements are always connected to each other by separate connecting pieces, some of which are leveling beams and some of which are fixed joints. In addition, the bases are connected to the rest of the pipe with different connections, so there are at least 3 different types of connections.

The various work steps at the installation site required run-: 35 saved heavy rolling stock and special tools. Due to the continuous installation location, this of course means 3 75416 inconveniences in changing terrain and thus very high additional costs.

The special solutions and materials used in the insulation of the support points (polyurethane + polyester) increase the total cost of the 5 support points by about 10 times per running meter, compared to the cost of the insulation elements of the rest of the pipe.

The elements in the curves have had to be shortened and it has not been possible to fasten them with an installation device, but the work has been done by hand.

The object of the invention is to provide a new insulation method which substantially eliminates the above-mentioned disadvantages and thus considerably reduces the installation costs.

The method according to the invention is mainly characterized in that at least the majority of the elements coming to the support structures are also installed directly in succession with glue joints, regardless of the location of each support structure of the cable relative to the insulating element coming from it, in order to secure the cable. and that the insulating element is cut open at the rim support members, and then mechanically closed so that the rim tensioning members are pressed into the insulator 25.

: Preferably, the insulating elements are connected to each other so that a part of the protective sheath formed at one end of the element, preferably with an inner seal, is closed around the end 30 of the adjacent element sheath, preferably with an external seal, and the insulating elements are positioned according to the terrain slope. is at the lower end of the element.

Also in a preferred embodiment of the method according to the invention, the longitudinal seam of the insulating elements can be closed mechanically by means of interlocking folds formed on the longitudinal edges of the protective sheath of the elements, as shown below with reference to the accompanying drawing and in claim 3.

In contrast to the known mechanical insulation method, which sought to use as long insulation elements as possible in order to minimize the number of joints, the method according to the invention uses rather short insulation elements, the maximum permissible transport width is generally 2.5 m. , very significant advantages are achieved which in many ways compensate for this disadvantage. The cable can be mechanically insulated in its entirety, including the support points and curves, with the same insulation elements and the same installation device, in particular the omission and continuous propagation of the special structures of the 15 support points significantly speeds up the work. The insulating element can be transported in a planar shape and unfolded by a conventional heavy-duty off-road vehicle, preferably using demountables, whereby the elements can be made into suitably sized "packages" already at the factory during installation. As the installation work and location progresses, the transport vehicle with its installation equipment easily follows. No adaptations are required, as well as usually no separate connecting pieces between the insulating elements. This is due to the fact that flexible weatherproof seals, either on the outer and / or inner surface of the sheet metal casing, are fitted at the factory in the vicinity of the transverse edges of the sheet metal casing of the insulating elements. Only on the ridge of hills and at the bottom of valleys, as well as on steep bends, which are few, however, leveling beams are needed if the protruding part of the protective sheath of each element is always at the lower end of the element. These leveling bellows are a type of rim known on the market, which is tightened with a light hand tool around the joint 5 7541 6 and fastened with self-drilling screws or rivets. However, especially if the slope of the terrain is gentle, a seal as good as the previous method is achieved even if the protruding part of the protective-5 jacket is at the upper end of the element.

The invention also relates to an apparatus for installing insulating elements, comprising means for lifting the insulating element from the transport carriage and jaws for closing the insulating element around the wire to be insulated.

The apparatus is characterized in that the outer edge of the closing jaws has openings dimensioned according to the support members of the support points of the cable to be insulated, so that the jaws can close around the cable at its support points. Preferably, the lifting members and the closing jaws are mounted on the boom crane via a grapple turner.

The invention will now be described in detail with reference to the accompanying drawing.

Figure 1 shows an embodiment of a support point in the longitudinal direction of the pipeline.

Figure 1A is an enlarged view of the tightening members of the pipeline mounting straps.

Figure 2 shows the same support point in cross section of the pipeline.

Figure 3 shows the insulation element used in the pipeline insulation solution in the mode of transport and seen from the outside.

Figure 4 shows the same in a transverse direction.

Figure 5 shows the same from the insulation side.

Fig. 6 shows an embodiment of the element in the longitudinal direction.

Fig. 6A shows a second embodiment of the element seen from the longitudinal direction.

Figure 7 shows the insulating element positioned at an inclined support point before compression, seen from the side.

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Figure 8 shows the same in the longitudinal direction.

Figure 9 shows an insulating element mounted in place at a support point, and parts of adjacent elements.

Figure 10 is an enlarged view of the joint between the shields of two successive insulating elements.

Fig. 10A shows the length seam of the element enlarged when the element of Fig. 6 is used.

Fig. 10B shows the longitudinal seam of the element in the case of the element according to Fig. 6A.

Figure 11 shows the installation apparatus.

Figures 12 and 13 show two embodiments of the clamping jaws of the mounting apparatus.

The support point comprises at the bottom a fixed structure carrying the pipe 1 and adjustable in the height direction 15, with two vertical supports 2 and 3 on both sides of the pipeline 1, longitudinal support beams 4 and transverse support beams 5. Parts to be fixed to the base are not shown here. On top of this 20 is placed a movable load-bearing structure 6, 7, which allows the pipeline to move according to temperature differences. The pipeline is fastened here with clamping straps 8, which are tightened around the pipe with bolted joints 9 as close as possible to it.

A preferred embodiment is shown in Figure 1A.

For each bolt 9, which preferably has a countersunk pin, a separate two-part sleeve holder 11 is used, which is welded to the rim 8 in its casing. The total contact surface of the protruding parts from the rim to the overlying insulation thus remains small, which facilitates pressing into the insulation as described below.

There is an insulating plate 12 between the rims and the pipe. The support point can also have a different structure, but according to the same sealed principle.

The insulating element 10 consists of a sheet metal protective sheath 13 and an insulator 14 attached thereto. A groove 15 is cut in the insulator 7 75416, which closes when the element is in place around the pipe. Weatherproof seals 17 and 18 are attached to the vicinity of one or both of the sealing edges of the protective jacket as shown in Figures 3, 4, 5, 6. The structural length of the element is selected according to the permitted transport width; generally this width is 2.5 m.

The insulating element 10 is lifted horizontally from the demountable 30 of the transport carriage 27 pulled by the towing vehicle 28 by means of the suction cups 25 in the mounting device 19 and placed on the pipe 1 at the desired position. Depending on the slope direction of the terrain in the longitudinal direction of the pipeline, the element is preferably turned so that water flowing along the pipeline flows over the protruding connecting parts 17 of the protective sheaths 13, such as on a roof covered with a roof tile.

15 The installation device 19 depends on the hydraulically operated so-called a grapple turner 20 which allows the mounting device to be conveniently turned. The grapple turner, in turn, is attached to a light hydraulically operated boom crane 26 attached to the mounting carriage 27. In the known methods, the mounting device depends on the hook of a separately moving conventional heavy lifting crane, and the element is turned by hand pulling with ropes attached to the mounting device.

When the element 10 is on the pipe 1 at the support point 25, openings are cut in it for the load-bearing structures 6. The element is then pressed around the pipe by means of the jaws 23 and 23 'of the hydraulically operated mounting device 19, which are articulated to a central arc 22 and which are driven by hydraulic cylinders 24 and 24'.

Depending on the structure of the fulcrum, one or two openings 29 for the supports 6 are formed in the outer edge of each jaw 23 and 23 '.

The edges of the sheath 13 of the element 10 which form the longitudinal seam of the element are preferably provided with interlocking folds 31, 32 and 33, 34, respectively, Figures 6, 6A and 10A, 10B. The outwardly folded folds, i.e. folds 31 and 33, are preferably double β 75416 folds, as shown in Figures 10A and 10B, to provide sufficient rigidity, while the inwardly folded folds 32 and 34 may generally be folded once. The closure of the longitudinal seams 5 will now be explained with further reference to Figure 8.

Assume that the outwardly directed fold 31 (or 33) of the element is on the right jaw 23 and that the inwardly folded 32 (or 34) is on the left jaw 23 ', in Figure 8. The jaw 23 is closed around the tube no-10 sooner than the jaw 23'. , so that the inwardly directed fold extends over and somewhat past the outwardly directed fold, whereby the insulation 14 becomes resiliently compressed in the circumferential direction of the pipe. The jaw 23 is opened, allowing the insulation 14 to expand and bring the outward-facing fold into engagement with the inward-facing fold, Figures 10A and 10B. Adherence to the grip ensures that when expanding in the circumferential direction of the pipe, the insulation at the same time presses the edge of the element outwards. The jaw 23 'is then opened and the next 20 elements are installed.

Thus, edge folds 31, 32 or 33, 34 can be used to form a permanent longitudinal seam; the seam remains reliably closed due to the resilience of the insulation and can be easily reopened if necessary, whereby the operations described above for the closing jaws 23 and 23 'are performed in the reverse order.

In the embodiment of Figures 6A and 10B, the outwardly directed fold 33 is located some distance from the edge of the shield 13 to form a guide or Liu-30 cup 35 for the inwardly folded 34 which protrudes more from the edge of the insulation 14 than the fold 32 of the embodiment of Figure 6, respectively. The jaw 23 ends before the fold 31 (or 33) and preferably the jaw 23 'also ends before the fold 32 (or 34).

The hydraulic devices required to achieve the above-described operation of the closing jaws 23 and 23 ', which actually control the functions of the hydraulic cylinders 24 and 24' connected to the jaws 23 and 23 ', are known per se, so that a detailed description of these devices in the context of this patent application 5 may be unnecessary. The terms "outward" and "inward" in the context of the interlocking folds 31-34 refer to the direction in which the fold is folded, i.e. away from the tube and towards it, respectively. With the length seam closed, the inward-facing fold 32 10 (or 34) is at the top.

Although the method of forming the longitudinal seam of the insulating element described above is quite advantageous because it is fast and eliminates a lot of manual work, the invention also includes the use of corresponding folds for temporarily closing the longitudinal seam 15, whereby the seam can be closed permanently, e.g. with self-drilling screws or rivets. completely close the longitudinal seams in a manner known per se.

The cut-out jacket parts 21 are cut to a suitable length and can be fastened with self-drilling screws or rivets to the box-like upper part 7 of the structure 6. Similarly, insulation is also installed on other sections of the pipeline, of course without open cuts in the absence of support structures 25.

A pipeline for such curves with limittäi lashing joints 16, 17, 18 (Figure 10), which operate the mechanical seal manner allowing the elements 10 movements between as shown by arrow A, can not be sealed, can 30 be used to separate additional seals or separate LII-of connectors, such as equalizing.

The method and apparatus according to the invention can, of course, also be used to insulate above-ground pipelines other than oil or gas pipelines, which are the primary uses.

Claims (6)

A method of insulating oil and gas pipelines intended to be built above ground in the terrain at certain intervals at intervals (2-6), wherein the conduit (1) is arranged on the support structures and is preferably attached thereto by by means of about the ninth connection (8) of the conduit and for the insulation of the conduit, a metallic protective sheath (13) and insulation element consisting of this insulation (14) is intended to be closed around the conduit (1) to be insulated; wherein the elements between the support structures are mounted one after the other with overlapping joints, characterized in that at least the majority of the elements coming in the support structures are mounted directly after each other with overlapping joints, regardless of the position of each support structure (2-6 ) for the conduit relative to the insulating element (10) coming into this, to use for the tensioning of the connections (8) attached to the conduit (1) attached to the conduit (1) is known per se substantially known to the clamping means (9) of the joints (8) of the joints (8) and that the insulating element is cut at the joints (6, 7) of the joints (8) and then sealed by mechanical means, so that the clamping members (9) are pressed in in the insulation (14). 2. A method according to claim 1, characterized in that the insulating elements (10) are connected to each other in such a way that a part (16) of the protective sheath (13) is provided with an inner seal (17). protruding from one end of the element, is closed around the end of the protective element of the adjacent element, which preferably has an outer seal (18), and the elements are applied in accordance with the end of the terrain s1, so that the protruding part of the protective jacket lies at the lower end of the element . A method according to claim 1, characterized in that