raw materials

The material used in the catheter is a stable composite material formed by adding polypropylene resin (PP) as the main body, adding other polyolefins and a small amount of antioxidants, stabilizers necessary to improve the life and additives that are conducive to improving the mechanics and processing performance of the catheter.

Raw material performance requirements

Polypropylene (PP) resin shall comply with the provisions of GB/T 12670, and other polyolefins, stabilizers, additives, etc. shall comply with the provisions of the corresponding national standards or industry standards.

color

It is generally orange and can also be agreed by both parties.

appearance

The inner and outer walls of the casing protection tube are smooth and flat, without bubbles, tears, cracks, peeling and obvious marks, depressions and the color is basically the same, the end face of the pipe is cut flat and perpendicular to the pipe axis, and the end face is smooth and free of burrs.

length

The length of each protective pipe is generally 6m or 9m, and it can also be agreed by both parties. The length limit deviation is +0.4%~0.2% of the length.

Protective tube connections

1. The connection method of hot melt welding on the end face is adopted between the protective pipes.

(1) For the hot welding process of the protective pipe, the construction personnel shall operate according to the requirements of the pipe and according to the relevant standards, and send it to the inspection department for joint profile inspection and tensile strength test.

(2) Before construction, the joint tensile strength test must be carried out, and three groups of joint samples should be drawn from the qualified pipe, and the joint test strength should not be less than 90% of the tensile strength of the pipe.

(3) Appearance quality inspection of the weld joint: directly observe the quality of the weld with your eyes, and check the size, shape and uniformity of the weld. Qualified weld buckles should have double reverse edges, uniform shape and size, no porosity, bubbling and cracks. The inner protrusion should be flat.

(4) Weld buckle profile inspection: the weld can be cut down, three samples can be cut along the axis, observe whether there are porosity and desoldering phenomenon in the section, and there should be no cracks at the bending 180º weld.

2. The connection mode of socket can also be used between the protection pipes according to customer requirements.

(1) The socket connection process is used to protect the pipes to ensure that the pipeline connection should pass the water seepage performance test.

(2) Socketed protective pipes are adopted, and the inner ports at both ends of each pipe have guide angles, and are smooth without protruding sharp objects to prevent scratching the outer sheath of the cable.