An article to understand polyurethane pre-insulated direct-buried foam insulation pipes | Yuanfeng

In modern energy transmission and industrial production, the insulation performance of pipelines is extremely important for the efficient use of energy and the stable operation of systems. Polyurethane pre-insulated direct-buried insulation pipes are becoming the preferred choice in many fields as an advanced insulation pipeline system.

Polyurethane pre-insulated direct-buried insulation pipes mainly consist of a three-layer structure. The innermost layer is the working steel pipe responsible for transporting various media. Depending on project requirements, seamless pipes, spiral welded pipes, or straight seam welded pipes can be selected. The surface of the steel pipe undergoes shot blasting rust removal treatment, achieving a high level of rust removal to ensure good bonding of subsequent processes. The middle layer is the polyurethane insulation layer, which serves as the core part of the insulation pipe. Using a high-pressure foaming machine, the raw liquid of rigid polyurethane foam is injected into the cavity between the steel pipe and the outer protective layer to form a “pipe-in-pipe foaming process.”

Polyurethane pre-insulated direct-buried insulation pipes have multiple advantages:

Outstanding insulation performance: Polyurethane foam has a low thermal conductivity, which significantly reduces heat loss during the medium transmission process, effectively reducing energy waste and improving energy efficiency.

Good mechanical properties: Using steel pipes as working pipes also gives this type of insulation pipe good pressure-bearing capacity and impact resistance, allowing it to adapt to various complex construction environments and operating conditions, ensuring the safe and stable operation of the pipeline system.

Excellent anti-corrosion performance: The outer protective pipe uses high-density polyethylene raw materials, effectively blocking the erosion of chemicals and microorganisms in the soil on the pipeline. Moreover, the high closed-cell rate and low water absorption rate of the polyurethane insulation layer further enhance the anti-corrosion ability of the pipeline, extending its service life.

Easy installation: The pre-insulated direct-buried insulation pipes are produced in a factory-prefabricated manner, requiring only simple joint treatment on-site. The installation process is simple and quick, which can significantly shorten the construction period and reduce construction costs.

Polyurethane pre-insulated direct-buried insulation pipes are widely used. In urban heating systems, they can effectively reduce heat loss, improve energy efficiency, and provide stable and efficient heating services for urban residents and enterprises. In the petroleum, natural gas, chemical, and other industrial fields, relying on their good insulation performance, they also ensure the stability of various process flows in production, ensuring the smooth progress of production.

With the deepening of energy-saving and environmental protection concepts and the continuous advancement of related technologies, the application prospects of polyurethane pre-insulated direct-buried insulation pipes will be broader. They will continue to play an important role in energy transmission and industrial production, contributing to the green development of various industries.

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  • Hebei Yuanfeng Pipeline Engineering Co., Ltd.
  • +86 4000-789-889 service@cnyufe.com
  • Building 34, Wanhe Mingzhu, Luquan District, Shijiazhuang City, 1-501.
  • Hebei Yuanfeng Pipeline Engineering Co., Ltd. was established in 2013 with a registered capital of 22.18 million yuan. It is a comprehensive R&D service enterprise focused on the production of steel jacketed steel direct-buried steam pipes, polyurethane direct-buried insulation pipes, spray-wound insulation pipes, galvanised iron overhead insulation pipes, PERT-II type insulation pipes, insulation pipe fittings, and joint installation. The company has strong production capabilities. Currently, it owns five production lines for polyurethane spray polyethylene wound prefabricated direct-buried insulation pipes, with an annual production of over 3,000 km of DN500mm-DN1600mm polyurethane spray polyethylene wound prefabricated direct-buried insulation pipes; 20 automatic winding machines for steel jacketed steel direct-buried steam insulation pipes, 8 sets of fully automatic pipe threading machines, 3 CNC intersecting line cutting machines, 2 pipeline fitting welding machines, 2 CNC plasma cutting machines, 10 external clamp cutting beveling machines, and 12 argon arc welders. It has 10 high-density polyethylene outer protective pipe production lines, with extrusion diameters reaching φ2000mm. The outer protective pipe production lines adopt advanced processes such as single-screw extrusion, vacuum sizing, corona treatment, spray cooling, and automatic cutting, capable of producing 30,000 tonnes of various types of high-density polyethylene outer protective pipes each year with diameters ranging from φ90-φ2000mm; 6 polyurethane prefabricated direct-buried insulation pipe production lines, 3 PU600 high-pressure foaming machines, capable of producing 5,000 km of DN20~DN1600mm insulation pipes; and 3 prefabricated overhead type polyurethane insulation pipe production lines, with an annual production of 2,000 km of DN25-DN1400mm prefabricated overhead type polyurethane insulation pipes. The company has production bases in Hebei, Inner Mongolia, Tianjin, and Liaoning, covering a total area of over 500 acres. The company's products cover China and more than 20 other countries and regions, including Mongolia, Russia, the Middle East, and South Africa. The products are mainly used for high-temperature steam transportation, central heating, and central cooling. Relying on advanced production technology, complete supporting equipment, and supply service systems, the company provides high-standard pipeline products to a wide range of customers, ensuring the safe operation of long-distance pipeline networks.

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  • Hebei Yuanfeng Pipeline Engineering Co., Ltd.
  • +86 4000-789-889 service@cnyufe.com
  • Building 34, Wanhe Mingzhu, Luquan District, Shijiazhuang City, 1-501.
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