FR2653852A1 - COAXIAL PIPE SYSTEM. - Google Patents

Abstract

The thermal expansions or contractions of the coaxial pipes are absorbed by intermediate anchoring pieces, which are connected to the ends of the rectilinear sections of a pipe and which are made up of integral cylindrical elements inside (1) and outside (2), presenting between them a disc (3) pierced with openings (4) for purging the pipe. Application in particular to pipes for transporting dangerous fluids.

Description

The present invention relates to a coaxial pipe system. In short,

  the invention adopts the conventional design of a pipe inside another pipe, which can be used to provide a secondary envelope for retaining dangerous fluids in long pipes with coaxial pipes having temperature differences between the pipes

outside and inside.

  Thermal expansions and contractions are absorbed by compressions and axial tensions in

  straight sections and not by bending or gondola-

  as in conventional lines. Inter-

  pipes and spacers anchors

  are used to automatically compensate for

axial lines.

  According to the present invention, a coaxial pipe system comprises an intermediate piece for anchoring the pipes, intended to be connected to the ends of these pipes.

  pipes and composed of integral one-piece cylindrical elements

  laughing and outside presenting between them an openwork disc

intended to allow a purge.

  In an advantageous embodiment, the wall of the internal cylindrical element has, over most of its length, a thickness greater than that of the pipes to which this element is intended to be connected, by welding for example. Furthermore, the length of this internal cylindrical element is greater than that of

the outer element.

  The invention will be described below in more detail, by way of nonlimiting example, with reference to the appended drawings in which Figures 1 and 2 are respectively a section - longitudinal - and an end view of a part. intermediate anchor; and FIG. 3 represents a part of a pipe with coaxial pipes comprising anchoring pieces between pipes. As shown in Figures 1 and 2, a room

  intermediate pipe anchor is composed of cylin-

  dres interdependent inside 1 and outside 2 having between them a perforated disc 3. This disc 3 is pierced with several openings formed in equidistant angular positions. This disc is disposed in the longitudinal direction substantially in the middle of the cylinders 1 and 2. The length of the cylinder 1 is greater than that of the cylinder 2. As shown, the thickness of the wall of the inner cylinder is advantageously greater, on the most much of its length, only at its ends. The ends 5 of the elements are advantageously chamfered to be

welded to pipes.

  Figure 3 shows the anchor pieces welded to the ends of a curved section of a coaxial pipe

  composed of interior and exterior pipes 6 and 7, respectively

  vement. To assemble the pipe, the inner pipe 6 is first welded to the cylinder 1 inside the part 8

  lower intermediate anchor. Then the pipe 7 outside

  laughter is adjusted on this inner pipe 6 and welded to the cy-

  outside liner 2 of this lower intermediate piece 8

  anchor. Hoses 6 and 7 have lengths

  read so that the opposite end of the inner pipe 6 exceeds the end of the outer pipe 7. This makes it possible to connect the upper intermediate anchoring part 9 to this projecting end of the inner pipe 6. Then, the end of the outer pipe 7 is connected, by a section of extension pipe, to the outer cylinder of this

  part 9 upper intermediate anchor.

  In addition to the above, a complete pipe line

  coaxial may still include external anchors

  riors, intended to immobilize the pipes at their posi-

  service. It is possible to have space on the length of the inner pipe 6 of the braces intended to support the outer pipe 7. It is possible

  - to make arrangements to connect conduits

  carrying pipes of different diameters and finally to close or seal, at the ends of a pipe, the space

  ring between pipes 6 and 7.

  The outer pipe 7 can serve as a secondary envelope.

  restraint. The openings 4 of the discs 3 of the pipe anchoring parts make it possible to purge the pipe at a low point, in the event of a leak in the internal pipe 6. In addition to its role of secondary retaining envelope, the external pipe 7 can carry out the insulation or allow the fluid to be heated or cooled using liquids or gases

  in the annular area between the coaxial pipes.

  Intermediate parts for anchoring the pipes

  put pipes of any length to expand or contract by thermal effect without changing their orientation to absorb these movements, or use a loop or elongation device such as expansion joints, toggle joints or with ball joints, or flexible hoses. When the pipe has been fitted, it requires practically no maintenance. The dilations

  and / or thermal contractions are absorbed by compression

  axial tension or tension of pipes and anchors instead of being bent or curled as in

classic lines.

  It goes without saying that it is possible, without departing from the scope or the spirit of the invention, to make modifications to the coaxial pipe systems shown.

and described.

Claims (4)

  1. Coaxial pipe system, characterized in that it comprises intermediate pieces for anchoring the pipes, intended to be connected to the ends of the coaxial pipes and each composed of solid cylindrical elements inside (1) and outside (2) having between them a perforated disc (3) so as to allow the system to be purged. 2. Coaxial pipe system according to claim 1, characterized in that the wall of the interior element   (1) has over most of its length a thick-   larger than that of the wall of the pipes which are intended to be connected to it.   3. Coaxial pipe system according to claim   1, characterized in that the length of the cylinder element   inner plate (1) is larger than that of the element external cylindrical (2).   4. Coaxial pipe system according to claim 1, characterized in that the ends of the elements (1, 2) are chamfered so that they can be welded to the pipes.