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There are two types of polyethylene foam: soft foam and hard foam. Soft foam has an open cell structure and is divided into two types: crusted and non crusted, while hard foam has a closed cell structure. There is another understanding of the material selection for polyethylene foam: different factors such as production materials, application purposes, application locations, construction methods, performance indicators, etc. can be classified into various types and shapes.

Polyethylene foam, due to its adjustable raw materials and density, especially its excellent thermal insulation performance, can be combined with other protective materials and has the advantages of good strength, light weight, and long service life, which can meet different needs. By using polyethylene foaming equipment to foam the cavity between the inner and outer pipes, the polyurethane solution is allowed to fully fill the cavity and form a hard polyethylene foam, which is tightly adhered to the inner and outer pipes, making it energy-saving, environmentally friendly, safe and reliable.

The soft foam material of polyethylene foam can only be used for on-site joint insulation after passing the pressure test. The construction quality of on-site joint insulation is unique to the construction of prefabricated buried pipelines and directly affects its service life. The insulation layer has a circular space for on-site polyethylene foam construction.

The hard foam of polyethylene foam can be worn in wet cotton jackets, greatly reducing the overall heat loss of heating pipelines. The heat loss of the heating network is 2%, which is less than the standard requirement of 10%. The outer shell has good anti-corrosion, insulation, and mechanical properties. The wall thickness of polyethylene foam can be adjusted, and the wall thickness and color can be produced according to user requirements. Due to the different wall thicknesses of pipes, the insulation layer thickness is approximate and should be calculated based on the actual thickness. It is suitable for repairing new or old roofs, especially for repairing old roofs. There is no need to remove the original waterproof and insulation layers, just remove the surface dust, sand and debris, and then spray paint. The construction is simple and fast, with a daily spraying capacity of over 200 square meters per job, which is conducive to catching up with the schedule.