RU2211397C2 - Pipe line - Google Patents

Abstract

FIELD: construction engineering; laying plastic pipe lines. SUBSTANCE: proposed pipe line includes thermoplastic pipes molded integral and reinforcing layers; thermoplastic layers are connected by welding. Thermoplastic and reinforcing layers of pipes are not fastened in at least zone of shrinkage stresses arising during welding over length equal to at least 10 thicknesses of thermoplastic layers from area of welding. EFFECT: enhanced reliability. 2 cl, 1 dwg

Description

 The invention relates to the field of pipes made of plastics made with reinforcement, more specifically to pipelines.

 A well-known pipeline containing pipes made of composite fiber material, connected by means of couplings and adhesive composition, see O. G. Tsyplakov. Designing products from composite fiber materials. - L .: Engineering, Leningrad Branch, 1984, p. 137, Fig. 4.16.6.

 The disadvantage of such a pipeline is its low sealing ability and short service life due to a breach of sealing.

 Another pipeline is known, containing pipes from monolithic thermoplastic and reinforcing with the connection of thermoplastic layers by welding - described in Japanese application 60-46310, MKI F 16 L 47/02 on "Method of joining plastic composite pipes".

 In terms of the totality of features and the achieved result, this pipeline is closest to the claimed one and adopted as a prototype.

 The sealing ability and service life of this pipeline due to the inner thermoplastic layer are significantly increased.

 However, the positive result achieved in this pipeline is insufficient, since the stresses arising during welding of the ends of thermoplastic pipes lead to the predominant destruction of the pipe along the pipe welding zones during operation of the pipe.

 The objective of the invention is to increase the durability of the pipeline.

 To solve this problem, the pipeline will be improved, containing pipes from monolithic thermoplastic and reinforcing layers with the connection of thermoplastic layers of pipes by welding.

 The improvement consists in the fact that the pipes are made with non-bonded thermoplastic and reinforcing layers, at least in the area of shrink stresses arising from welding in thermoplastic layers.

 In an embodiment, the pipes are made with non-bonded thermoplastic and reinforcing layers at a length of at least 10 thicknesses of thermoplastic layers from the place of their welding.

 The execution of the ends of pipes with non-bonded thermoplastic and reinforcing layers at least in the area of shrinkage stresses that occur during welding in thermoplastic layers, reduces the residual welding stresses in the thermoplastic layers of the connected pipes, which increases the durability of the pipeline.

 The implementation of pipes with non-bonded thermoplastic and reinforcing layers at a length of at least 10 thicknesses of thermoplastic layers from the place of their welding ensures the location of monolithic pipe sections beyond the zone of shrink stresses of the thermoplastic layers being welded, depending on the thickness of the latter.

 Below with reference to the drawing describes the pipeline according to the invention.

 The proposed pipeline contains pipes 1 of monopoly by means of sevilen 2 thermoplastic 3 (polyethylene) and reinforcing 4 (fiberglass) layers with a connection of thermoplastic layers 3 with a weld 5.

 Pipes 1 are made with non-bonded (non-monolithic) thermoplastic 3 and reinforcing 4 layers at least in zone A of the shrinkage stresses arising during welding in thermoplastic layers 3 (due to which residual welding stresses in the thermoplastic layers of the pipes being welded are reduced).

 In the embodiment, the pipes 1 are made with non-bonded thermoplastic 3 and reinforcing 4 layers at a length of at least 10 thicknesses B of thermoplastic layers 3 from the place of their welding — weld 5 (due to which the monolithic sections of the pipes are located beyond the zone of shrink stresses of the welded thermoplastic layers).

 During operation of the pipeline due to a decrease in welding stresses in the thermoplastic layers 3, the service life of the latter increases.

 The implementation of the pipeline according to the invention provides a significant (up to 30%) increase in its service life without repair, that is, durability.

Claims (2)

 1. A pipeline containing pipes from monolithic thermoplastic and reinforcing layers with a connection of thermoplastic layers by welding, characterized in that the pipes are made with unshaped thermoplastic and reinforcing layers at least in the area of shrink stresses arising during welding in thermoplastic layers.  2. The pipeline according to claim 1, characterized in that the pipes are made with loose thermoplastic and reinforcing layers at a length of at least 10 thicknesses of thermoplastic layers from the place of their welding.