Stock material or miscellaneous articles – Hollow or container type article – Polymer or resin containing
Patent
1989-06-05
1991-12-31
Seidleck, James J.
Stock material or miscellaneous articles
Hollow or container type article
Polymer or resin containing
428258, 138125, B29C 2716, B32B 700, F16L 1100, F16L 5518
Patent
active
050771078
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a lining material for lining the inner surface of pipelines, such as gas conduits, city water pipelines, sewage pipelines, pipelines for laying power transmission wires or telecommunication cables, and petroleum pipelines, etc., chiefly those buried in the ground, for the purpose of maintenance and repairs or reinforcement thereof.
DESCRIPTION OF THE PRIOR ART
In recent years, a method of applying a lining material onto the inner surface of various kinds of pipelines, such as city water pipelines, sewage pipelines, gas conduits, pipelines which accommodate power transmission cables or telecommunication cables and oil pipelines, etc., has been carried out for the purpose of maintenance and repairs or reinforcement of the pipelines when they are superannuated. The method of applying a lining material is carried out in such a manner that a tubular, flexible lining material whose inner surface has previously been coated with an adhesive is inserted into a pipeline and allowed to advance therein while turning the lining material inside out and pressing it against the inner surface of the pipeline under a fluid pressure, whereby adhesively bonding the inner surface of the lining material onto the inner surface of the pipeline. This method of application is advantageous in that there is no need for digging up pipelines already laid over the entire length thereof for the purpose of application of the liner, and the lining work can be done within a short period of time for a long pipeline and also can be applied even to a pipeline having a number of bends, thus attracting attention especially in recent years as an extremely excellent method.
A pipeline whose inner surface has been applied with a lining material is of a construction wherein another pipe formed by the lining material layer exists inside the outer pipe, i.e., so-called pipe-in-pipe construction, and therefore even when the outer pipe is damaged by the action of external forces, the inner pipe formed by the lining material layer is still intact and effective to prevent the leakage of the fluid contained therein, thereby ensuring that a flow path for the internal fluid is secured temporarily.
In such a case, it is required that the pipeline should have a satisfactory earthquake resistance property wherein even when the outer pipe is damaged by external forces, the inner pipe formed by the layer of the lining material applied to the inner surface of the outer pipe is not destroyed and still effective to prevent the leakage of the fluid therein. Thus, the main phenomena which take place in the event of the damage or breakdown of a pipeline include peripheral cracking and fracture of the pipe and detachment of pipe joints fitted thereto. Therefore it is required that the lining material should have sufficient strength in the longitudinal direction of the pipe and be able to exhibit an elongation of about 10 to 20%.
In case a pipeline is damaged by earthquake etc., external pressures such as underground water pressure and earth pressure act directly on the inner pipe formed by the lining material layer, and therefore it is required that the lining material should have sufficient strength to withstand the underground water pressure and the earth pressure; that is, a satisfactory shape retaining property against external pressures. This shape retaining property against external pressure contributes to a great degree to the circumferential bending modulus of elasticity of the lining material forming the inner pipe. Thus, the greater the bending modulus of elasticity, the better the shape retaining property of the above-mentioned inner pipe against external pressures.
Further, when a fluid under pressure is transported through the pipeline, it is required that the inner pipe formed by the lining material layer have strength enough to withstand the internal fluid pressure. Therefore, the coefficient of expansion in diameter of the inner pipe due to internal pressure should preferably be as small as poss
REFERENCES:
patent: 4684556 (1987-08-01), Ohtsuga et al.
Kaneda Shigeo
Morinaga Akio
Saito Hitoshi
Seshimo Masahiro
Ashimori Kogyo Kabushiki Kaisha
Nold Charles R.
Seidleck James J.
Tokyo Gas Kabushiki Kaisha
LandOfFree
Lining material for pipelines does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Lining material for pipelines, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Lining material for pipelines will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1509129