The commonly used connection methods of polyethylene composite pipes with steel wire mesh skeleton for coal mines include electric melting connection, flange connection, clamp type quick connector connection, looper flange type quick connector connection and plate type flange type quick connector connection with neck. The following is a detailed introduction to these connection methods:

electric melting connection:

principle: the composite pipe is inserted into the electric hot melt pipe fitting, and the electric heating wire embedded in the inner surface of the pipe fitting is energized to generate heat. First, the inner surface of the pipe is melted to produce a melt, and the melt expands and fills the gap between the pipe fittings until the outer surface of the pipe also produces a melt, and the two melts are melted together. After cooling and forming, the pipe and the pipe fittings are tightly connected as a whole.

advantages: high connection strength, good sealing, suitable for pipe connection of various specifications.

operation: cut the pipe vertically to ensure that the pipe has sufficient hot melt area; Grind off the oxide layer of the connection port, remove dirt after grinding, mark the depth line, and prepare the sleeve; Casing, sleeve the pipe to the specified scale, and then connect with the welding machine; Calibration, ensure that the pipe and pipe fittings are on the same axis to avoid deviation; Power welding, strictly abide by the specified power on time, voltage parameters; cooling, after welding, it is necessary to keep the clamp locked, do not move, and cool naturally.

flange connection:

principle: the two pipes are respectively fixed on the two flanges, the two flanges with flange pads in the middle, and then use bolts to tighten the two flanges to combine them.

advantages: convenient connection, suitable for pipeline systems that require frequent disassembly or maintenance.

operation: connecting flange and pipeline, the center of the two needs to be in a horizontal line, and the center of flange sealing surface and pipeline needs to be vertical; Gasket flange gasket, the same pressure flange of the same pipeline shall be selected with the same gasket; Before connecting the flange, make sure that the sealing surface is smooth and free of burrs, the thread is complete and free of defects, and the gasket surface is free of defects. Before flange assembly, ensure that the center of the pipeline is perpendicular to the sealing surface, and the bolts of the same specification are installed in the same direction. If the flange needs to be buried in the ground, anti-corrosion treatment should be done in advance.

clamp type quick coupling connection:

principle: press the clamp type quick connector to both ends of the steel wire mesh skeleton pipe and connect it with flexible groove pipe fittings.

advantages: fast connection speed, easy operation, suitable for occasions requiring quick installation.

Loop flange type quick coupling connection:

principle: press the looper type quick connector to both ends of the steel wire mesh skeleton pipe, seal with rubber gasket, and fasten the flange evenly through bolts during connection.

advantages: It combines the advantages of flange connection and quick connector, which not only ensures the strength of the connection, but also improves the speed of the connection.

plate with neck flange type quick coupling connection:

principle: steel wire mesh skeleton pipe with neck flange type quick joint at both ends, so that the pipe has the flexibility of plastic pipe, but also has the rigidity of steel pipe joints. Use bolts to fasten the flange evenly when connecting.

Advantages: Suitable for occasions with high requirements for pipeline rigidity and sealing.