Radiation cross-linked polyethylene thermal expansion pipe and manufacturing method

Abstract

The invention relates to a radiation cross-linked polyethylene thermal expansion pipe and a manufacturing method. The methods, products and techniques of the existing lined plastics of pipelines have defects. The radiation cross-linked polyethylene thermal expansion pipe provided by the invention comprises the following components in parts by weight: 100 parts of linear low density polyethylene (LLDPE), 30 parts of high density polyethylene (HDPE), 20 parts of low density polyethylene (LDPE), 10 parts of ethylene-vinyl acetate (EVA), 0.8 part of tetra(beta-(3, 5-bibutyl-4-hydroxyphenyl) propionic acid) pentaerythritol ester and 0.6 part of black masterbatch, wherein the mixture capable of carrying out radiation cross-linking is prepared into a polymer pipeline. The radiation cross-linked polyethylene thermal expansion pipe provided by the invention can be used for the field joint repair of a coating in a pipeline, the corrosion resistance and scale resistance in the pipeline, the pipeline repair with pitting corrosion, the lining in a special liquid conveying pipeline and the like.

Description

Technical field: [0001] The invention relates to a plastic pipe made of radiation cross-linked polyethylene and having the function of diameter expansion after heating, in particular to a radiation cross-linked polyethylene heat-expandable pipe and a manufacturing method. Background technique: [0002] At present, domestic and foreign internal pipeline anti-corrosion technologies are mainly concentrated in two aspects: one is pipeline internal coating technology, and the other is pipeline plastic lining technology; coating technology has been reported a lot in China, of course it has many advantages, such as low cost; and Plastic lining technology has risen with a new attitude in foreign countries; there are deficiencies in the existing methods, products and technologies for plastic lining of pipelines: for example: Chinese patent CN1051783A describes that a section is larger than the inner diameter of the pipeline to be lined and has the ability to maintain When a tube made...

AI Technical Summary

Problems solved by technology

[0002] At present, domestic and foreign internal pipeline anti-corrosion technologies are mainly concentrated in two aspects: one is pipeline internal coating technology, and the other is pipeline plastic lining technology; coating technology has been reported a lot in China, of course it has many advantages, such as low cost; and Plastic lining technology has risen with a new attitude in foreign countries; there are deficiencies in the existing methods, products and technologies for plastic lining of pipelines: for example: Chinese patent CN1051783A describes that a section is larger than the inner diameter of the pipeline to be lined and has the ability to maintain When a tube made of resilient plastic material is pulled through a mold or roller, its outer diameter is reduced by 15% and pulled into the pipeline to be lined, using force to produce elastic deformation of the material, making it have a short-term memory effect, to be removed After the tension, the pipe will naturally recover its expansion diameter and closely fit the inner wall of the pipe; this method must be operated on the construction site and requires large-scale special equipment; the technology described in CN1785651A can make the outer diameter of the PE pipe larger than the inner diameter of the steel pipe through the multi-U-shaped pipe technology After the PE pipe is reduced in diameter, it is drawn into the steel pipe, and after recovery, it fits on the inner wall of the steel pipe with an interference fit. This technology is similar to CN1051783A in that the plastic pipe is temporarily deformed, and then the deformed pipe is lined into the pipe that needs to be lined; Some patents are related to products. For example, the technology described in Chinese patent CN2420481Y can use a thin-walled hose made of molecularly grafted high-density polyethylene material. Hot melt adhesive is compounded on the outer wall of the thin-walled hose. After the cross-linking reaction, the pipe is cross-linked and hardened, and it is bonded to the inner wall of the pipe by hot melt adhesive

This technology does not use the memory effect of the material, but uses a pressurized method to expand the tube and then combines it with the inner wall of the tube by hot melt adhesive

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