The horizontal contact surface between the hook and the end of the spiral steel pipe shall not be less than 40mm, otherwise it will easily deform the nozzle and affect the connection of the pipe.

Round steel refers to a solid strip of steel with a circular cross section. Its specifications are expressed in diameter, in millimeters (mm), such as "50mm" means a round steel with a diameter of 50 mm.

Plastic-coated composite steel pipe is also called plastic-coated steel pipe. Plastic-coated steel pipe is a steel-plastic composite product with steel pipe as the base pipe, plastic powder as the coating material, a plastic layer on the inner surface, and a plastic layer or other anti-corrosion layer on the outer surface. .

Spiral steel pipe (SSAW pipe) is a spiral seam steel pipe made of strip steel coil as raw material, extruded at regular temperature, and welded by automatic double-wire double-sided submerged arc welding process. The spiral steel pipe sends the strip steel into the welded pipe unit, and after rolling by multiple rollers, the strip steel is gradually rolled up to form a circular tube blank with an opening gap. Adjust the reduction amount of the squeeze roller to control the gap between the weld seams at 1~3mm, and make the two ends of the weld joints flush.

The inspection and inspection of the quality of the billet and the necessary cleaning of the surface defects of the billet are the basic prerequisites to ensure that the blanks used in the production of seamless steel pipes meet the quality requirements.

There are many ways to link steel pipes (such as seamless pipes and welded steel pipes), and the commonly used ones are:Compression type, union type, compression type, pusher type, taper thread type, socket welding type, union type flange connection, welding type and derivative series connection methods combining welding and traditional connection.