Description :: Our patents

The guessed invention falls into field of pipelines running and can be used in field requirements: steppes, desert, taiga, etc., with usage of laser welding.

It is known, that in field requirements the pipelines running, predominantly main-line, is carried out usually in line. That is some separate pipelines (branch lines) are welded with outside circular seams, for example, by a contact technique [1], and are placed on specially for this purpose readied legs on particular distance from each other. Before placing of pipeline branches are carried out following operations: a partial leveling of terrain contour there, where will transit pipeline route, removal of a wood cover (in taiga) and etc. Thus breadth of prepared route depends on quantity of pipeline separate branches, and also from distance between them. Minimum distance between pipeline branches is defined basically with construction and dimensions of welded device, overlapping a pipeline and a tube, welded on it. The quantity of legs depends on pipeline hardness and terrain contour.

To disadvantages of pipelines running conventional technique treat:

A necessity of major volume of preliminary operations, bound with major breadth of prepared route, that in turn is bound with high primary material inputs.
An applying of major injury to ecology of regions, on which will transit pipeline route, bound with:
1. A necessity of cutting down of wood arrays major areas (at pipeline running in taiga);
2. Local variations of climatic conditions, bound with oil transporting in terrain with a cold climate. On particular distances along pipeline route it is necessary to mount installations for oil preheating. And at transporting natural gas, which is warming up a pipeline (friction about interior walls) are mounted installations for gas cooling. Besides, the installations for oil preheating, and also pipeline with heightened outside temperature in requirements of a permafrost, promote soil defrosting, that carries on to stability loss of beds of pipeline legs and installations for oil preheating. It can bring to intolerable bends and, therefore, to breaks of pipelines.
For lowering action of negative factors, bound with heightened temperatures of a pipeline, concerning a surrounding medium, at conventional technique of running it is necessary to isolate each separate pipeline branch, that demands a heavy expense of an insulating material, and also major expenditures of time on isolation operations holding.
Hardness of pipeline separate branches is low-level. This circumstance carries on that along a route it is necessary to erect major number of legs. Also thus there are problems at natural hindrances crossing with pipeline route - small rivers, ravines, etc.

Problems, solved by this guessed invention, are lowering material, and also labour intensity, bound with pipeline running, diminution of parasitic influence on surrounding medium ecology, expansion of pipeline operation capabilities, magnification of pipeline hardness.

The above-stated problems are solved by that pipeline running is carried on with an arrangement of its separate branches in a compact beam with minimum distance between them. Tubes welding to pipeline branches is carried on inside of tubes with a laser beam, and a distance between tubes of separate branches is minimum, and contiguous outer tubes of a compact beam are welded by a main seam on all length of welded tubes with S-polarized radiation.

Arrangement of pipeline separate branches in a compact beam with minimum distances between them allows reducing sharply volume of preliminary operations because of essential diminution of made route breadth, diminution of quantity of necessary legs. Thus is reduced the injury, applied to surrounding medium ecology.

The beam hardness of tubes, welded among themselves, is higher than separate tube hardness - the danger of pipeline breaking is reduced, the quantity of necessary legs is diminished. Usage of S-polarized radiation allows increasing essentially an efficiency of laser welding process.

Besides, arrangement of pipeline separate branches in a compact beam with minimum distances between them enables to realize all beam isolation, instead of each tube separately. That essentially reduces quantity of necessary insulating material and expenditures on its packing as contrasted to running conventional technique. For example, for running of pipeline, consisting from seven branches, with conventional technique (see fig.2) the area of necessary insulating material is peer: S_m = p D L 7;

where: D - diameter of a tube;

L - pipeline length.

At an offered technique of running (figs. 1 a). and b).), the area of necessary insulating material is peer:

For a case a).: S₁ £ 3p D L;

For a case b).: S₂ = (p D+4 2D) L.

Given calculations show, that the area of demanded insulating material is reduced in 2 and more time as contrasted to running conventional technique. The volume of operations, necessary for holding pipeline protection is accordingly reduced also.

Arranged in compact beam pipeline branches with uniform isolation have a major heat capacity, than separately arranged branches, that allows in that case to lower working costs, bound with necessity of transported material preheating (for example, oil transporting in tundra requirements).

The arrangement of pipeline branches in a compact beam allows also essentially to expand its technological opportunities at transporting through it different loads with simultaneous lowering of working costs. For example, (see fig.1) oil transporting through central branch, requiring periodic preheating, and gas – trough peripheral branches, requiring periodic refrigeration (or inversely), allows fractionally to cancel temperature gradient, appeared between them. Gas, heated because of friction about interior walls of a pipeline, through walls transfers the heat to an oil pipeline. The gas line thus is cooled, and the oil pipeline, inversely, is heated.

It is known, that in requirements of desert the supply of separate regions with potable water is a major problem. The offered technique allows to solve a problem of water delivering in places, deleted from a coast, from coastal areas, where desalting of sea water is carried out. In a beam of pipeline branches the central branch transits fresh water to oil deposit. The peripheral branches carry on oil (petroleum products) in an opposite direction - from a deposit to coastal areas, where is carried out their transporting to places of their consumption. In this case a branch, leading water, does not exposed to a direct action of solar radiation, is heated less and promotes refrigeration of peripheral branches. To more effective refrigeration of oil peripheral branches promotes that circumstance, that the oil has maximum temperature at the end of transporting path (final piece of the pipeline), i.e. there, where the water has minimum temperature.

Arrangement of pipeline branches in a compact beam with minimum distance between them (down to their touch one another) is possible only in case of inside welding tubes, i.e. when all devices of a welding set during welding are inside a welded tube and pipeline.

The realization of separate branches welding with an outside circular weld with their subsequent superposition in a compact beam practically is impossible because of enough high hardness of pipelines under bending, their major diameters [2] and masses of branches ends.

The known welding complex for manufacture of continuous pipeline [3] incorporates intratube welding machine with self drive unit of transposition and ladder-type rod, automotive car with power station, control equipment, inductor, roller conveyer, container for intratube welding machine, platform with clamps, disposed on it. The tube, intended for welding, is erected in clamps, arranged on a uniform platform with clamps of pipeline end. An added installation of their ends is not required. After that, using self drive unit, intratube welding machine goes to a bore of welded tube, moves inside it up to a junction place and carries out a circular weld. After welding the intratube welding machine moves to an exit. After moving from a tube, it moves in the container. The welding complex moves forwards on length of a tube. The charging of a new tube is further yielded, its centering concerning the pipeline and work cycle is iterated.

The given complex allows to conduct welding inside of tubes and to realize pipeline running in a compact beam. By this are excepted above-stated disadvantages of pipeline running with a conventional technique.

However, usage of this complex has following disadvantages, which are not permitting to apply it in an offered technique of pipelines running.

It is known, that in practice there are two techniques of welding, permitting to achieve higher service properties of a weld (minimum amount of crystal defects, higher plasticity, impact elasticity, etc.) - as contrasted to base metal - laser and electric beam techniques. All remaining techniques, including arc, used in above described welding complex, aggravate service properties of weld metal, as contrasted to base metal properties ([4], [5], [6]). In an offered technique of pipelines running this circumstance is defining, as, if service properties of welds are worse than service properties of a base metal, the welds will be a place of different flaws origin and, therefore, cause emergencies of pipelines. As the liquidation of pipeline emergencies consequences, made in a compact beam, is much more complicated, than a pipeline, made with a conventional technique, usage of other welding techniques, except laser and electric beam is unrealizable in an offered technique.

Therefore techniques of welding, at which service properties of connections are not aggravated and even are improved a little, thereby use reliability of all pipeline remains at a former level or is incremented a little, allow to implement an offered technique of pipelines running. The emergencies on pipelines, happening on a base metal are eliminated practically.

Usage of electric beam welding in an offered technique is impossible practically, as for its embodying it is necessary to make high vacuum cavities on interior and exterior side of pipeline welded elements, that in field requirements it is very complicated to realize technically and demands also expenditures of time. Besides, vacuum cavity availability increments minimum distance between beam branches, that is essential depreciated an advantage of running offered technique.

The laser welding does not demand availability of vacuum cavities in a welding zone and so technical difficulties and added expenditures are excepted. An absence of any devices of welded installation on welded pipeline exterior side allows bringing together its branches on minimum possible distance among themselves.

The offered technique can be implemented in different variants of positional relationship of pipeline branches. On fig.1, a). is shown the arrangement of pipeline branches on radius with one central branch. On fig.1, b). Is shown the rectangular arrangement of pipeline branches. Fig. 2 displays a conventional arrangement of pipeline branches –in line.

Labeling: pos.1 - legs;

pos. 2 - pipeline central branch;

pos. 3 - pipeline peripheral branch;

pos. 4 - pipeline insulating material.

The installation for embodying of pipeline running technique in a compact beam looks like this (fig. 3, fig. 4, fig. 5). Tubes 6, intended for a welding to the pipeline 5 are erected in replaceable boxes 7, 8. Replaceable boxes incorporate beam guides (or laser oscillation blocks) 9 with focusing devices 10, and also with rotation drives around of tube axis (are not shown). The transposition drive unit 11 allows to realize boxes change. The composition of installation is entered also technological laser 12, radiation supply system in beam guides 13, consisting from deflecting mirrors, system of radiation transporting and drive units. The management of installation is carried out with the help of a uniform control system 14. All processing equipment is arranged on a moving platform 15 and moves with the help of a moving mean 16.

Structurally radiation supply system can be fulfilled in different variants. On section B-B (fig. 5) is shown one variant of radiation delivery in a tube beam with radial distance of pipeline branches. The laser beam from the technological laser 12 is guided on a deflecting mirror 17, being reflected from which one on system of radiation transporting 18 is guided on other deflecting mirrors 19, then is guided to a beam guide 9. The replaceable boxes 7, 8 have also overlapping construction 20 with the exterior beam guides 21, arranged on radius, on ends of which the stationary focusing devices 22 are anchored.

The installation operates as follows. On beam guides (laser oscillation blocks) 9 of replaceable box 8 are erected tubes 6, intended for welding.

The construction of replaceable boxes is fulfilled so, that, after installation on beam guides (laser oscillation blocks) tubes, their installation and their relative position coincides with relative position of pipeline branches ends. After installation of tubes in replaceable box, transposition drive unit 11 transits the box to the pipeline 5. Thus axes of tubes, set in the box, coincide with axes of tubes of pipeline branches (standing is shown on fig. 4). The radiation supply system 13 by a command of uniform control system 14 sequentially guides laser radiation from technological laser 12 in each tube, where it on beam guides 9 is guided to focusing devices 10. The rotation drive of the focusing device rotates it around of pipeline axis, so that they outline a closed – type circle on welded junction. Thereby is made a tube welding to a pipeline branch with a circular weld. Simultaneously is carried out a charging of replaceable box 7 with tubes. After a welding of all tubes of replaceable box 8 is carried out the transposition of installation forwards on a course of a route on distance, equal to a length of welded tubes. Thus beam guides (the blocks of oscillation) leave from just welded tubes. After that, with the help of transposition drive unit 11 the box 8 displaces to the side (on figs. 4 – broken lines). Further transposition drive unit 11 transits the box 7 to the pipeline and the work cycle of plant operation is iterated.

Thus, as contrasted to conventional technique of pipeline running (fig. 2), the offered technique allows essentially to lower expenditures on route preparation by diminution of its breadth, to lower quantity of injury, caused to a surrounding medium, to reduce quantity of an isolate material. The pinch of pipeline heat capacity at an arrangement of its branches in a compact beam allows essentially lowering a volume of delivered heat for petroleum products preheating in requirements of low temperatures.

The close relative position of pipeline branches, permitting to realize heat transition from one branch to other, enables to cancel mutually temperature gradients, applying at transporting of different products through the pipeline and thereby to improve reliability of its operation and to lower operating cost.

What is claimed is:

A technique of pipeline running, comprising route preparation, legs installation, sequential tubes welding to separate pipeline branches, characterized in that tubes welding to separate pipeline branches is carried on inside, in a compact beam, with minimum distance between them, by a circular weld, with the help of laser beam, and exterior contiguous tubes are welded simultaneously among themselves, by main seam, on all length of a tube.
The technique of pipeline running according to claim 1, wherein the isolation of all pipeline branches is common.
An installation of pipeline running technique according to claim 1, wherein are had replaceable boxes, comprising interior beam guides, transiting inside welded tubes, and exterior beam guides.
The installation according to claim 3, wherein the tubes axes, set on replaceable boxes, coincide with axes of pipeline separate branches.
The technique according to claim 1, wherein the liberation of replaceable box from tubes, welded on the pipeline, is carry on simultaneously with welding of exterior contiguous tubes.