The Polyurethane (PUR) Spray Polyethylene (PE) Wrap Pre-Insulated Pipe Production Line is designed for manufacturing polyurethane pre-fabricated direct-buried thermal insulation pipes. These pipes are widely used in:

• District heating networks
• Industrial cooling systems
• Crude oil and chemical transportation pipelines

• Anti-corrosion & thermal insulation pipelines for heating, cooling, and crude oil transportation
• Medium temperature: ≤ 120°C (peak ≤ 140°C)
• Medium pressure: ≤ 2.5 MPa
• Installation methods: Direct burial (primary), trench laying, or overhead installation

1. The density, thermal conductivity, compressive strength and other indicators of the polyurethane insulation layer are uniform and consistent, and the overall performance of the product is good.
2. The polyurethane insulation layer is formed by free foaming, and the direction of bubble initiation is perpendicular to the axial direction of the pipe, which improves the compressive strength of the insulation layer.
3. The polyurethane insulation layer is formed by spraying, and the raw materials are sprayed onto the outer surface of the steel pipe/piece in liquid form, and then initiated. Due to the high reactivity of the sprayed polyurethane raw materials, their adhesion to the steel pipe/piece is higher.
4. The surface of polyurethane foam is rough, which is more conducive to the bonding effect between the insulation layer and the outer protective layer.
5. Polyurethane insulation layer can be sprayed according to the thickness required by customers and designs, with a thickness of up to 15-20mm, greatly saving customers' costs.
6. Prefabricated buried insulation pipes produced using the "spray wrapping" process can adjust the thickness of the polyurethane insulation layer and polyethylene outer protective layer according to user needs, and the production process does not require the addition of corresponding molds and fixtures, making it simple and easy to implement. Due to the absence of expansion stress on the polyethylene outer protective layer during foaming in the "spray wrapping" process, the thickness of the polyethylene outer protective layer can be made relatively thin, reducing customer cost investment.
7. The polyethylene outer protective layer is formed by circumferential winding, and its circumferential elongation and tensile strength indicators are significantly improved due to the influence of process stretching, resulting in better quality.
8. Due to the use of fully automated production lines, the spray wound insulation pipes/pieces produced by the company are superior to the typical spray wound insulation pipes/pieces on the market in terms of product quality and various performance indicators.

The spray and winding production process ensures:

• Uniform insulation layer density
• Improved product quality
• Optimized production efficiency
• Lower production costs

1. Steel Pipe Outer Wall Shot Blasting Line

   • Prepares steel pipe surface for optimal polyurethane bonding

2. Polyurethane Spray Molding Line

   • High-pressure spray technology for uniform foam application

3. Polyethylene Sheet Extruding & Winding Line

   • Continuous extrusion and spiral winding of PE casing

4. Water Cooling Line

   • Controlled cooling for dimensional stability

5. End-Cutting Equipment

   • Precision trimming of finished pipes

     Our company

     Qingdao Huashida Machinery Co., Ltd was established in 2003 and has focused on plastic pipe extruder production line and joints of plastic pipes and 2PE 3PE pipes machinery for over 16 years. We are a private high-tech enterprise integrated by R&D, manufacturing, selling, service and trading.

     We are always concentrating on research and development of plastic extrusion equipment, tightly cooperating with Tsinghua University, Beijing University of Chemical Technology, South China University of Technology and some other colleges and scientific research institutions. Meanwhile, by absorbing advanced technology home and abroad, we have been one of the top manufacturers of plastic extrusion machines in China, especially of PE insulation jacket pipe extrusion line, PE PP sheet extrusion line, and PE hollow wall spiral pipe production line.

     Customer Cases