Corrosion-resistant and heat-insulating pipes are composite pipes with anti-corrosion treatment on the outer surface of steel pipes and an added heat insulation layer. They have excellent corrosion resistance, heat insulation performance and service life, and are widely used in pipeline transportation fields such as oil, natural gas, heating and chemical industries.
3PE anti-corrosion pipe Product Standards: Polyethylene Anticorrosion Coating for Buried Steel Pipelines GB/T23257-2017; Technical Specification for Fusion-Bonded Epoxy Powder Coating for Steel Pipelines SY/T0315-2013 Applications: Widely used in buried pipeline projects in industries such as petroleum, natural gas, chemical, and urban water supply, extending pipeline lifespan to 30-50 years. Product specifications: DN50-DN1420mm, three-layer polyethylene (3PE), two-layer polyethylene (2PE), single-layer epoxy powder (FBE), double-layer epoxy powder (2FBE) Product Advantages: X-ray and hydrostatic testing of the base pipe; 3PE anti-corrosion technology combines the advantages of epoxy and polyethylene anti-corrosion layers, with an inner coating of food-grade epoxy powder, possessing high mechanical strength, wear resistance, corrosion resistance, temperature resistance, and pressure resistance; Combining the mechanical properties of steel pipes with the corrosion resistance of high-molecular polymers, extending service life, it is an advanced water transmission pipeline. The 3PE anti-corrosion layer is an ideal protective layer for buried pipelines.
Ø 3PE anti-corrosion (three-layer polyethylene) technology is an advanced anti-corrosion technology introduced from abroad. This method uses a fusion-bonded epoxy (FBE), polyethylene copolymer adhesive, and polyethylene to form an integrated anti-corrosion layer. The basic principle is to use fusion-bonded epoxy (FBE) for corrosion protection, while polyethylene protects the anti-corrosion layer, and the adhesive bonds the anti-corrosion layer and the protective layer. Ø 3PE anti-corrosion structure: First layer epoxy powder (FBE>100um), second layer adhesive (AD) 170~250um, third layer polyethylene (PE) 1.8~3.7mm. The three materials are fused together and firmly bonded to the steel pipe to form an excellent anti-corrosion layer. Ø Three-layer polyethylene anti-corrosion is one of the main technical systems for external anti-corrosion of buried pipelines both domestically and internationally. It has good anti-corrosion performance, low water absorption, and high mechanical strength, and has been increasingly widely used in buried water, gas, and oil pipelines in China in recent years. 3PE anti-corrosion pipe production process 3PE anti-corrosion coating wrapping and testing
Polyurethane foam prefabricated direct-buried insulation pipe Execution Standard: CJ/T114-2000 - "High-Density Polyethylene Outer Sheath and Polyurethane Foam Precast Direct-Buried Insulated Pipe" Application Scope: Insulated pipes are widely used in liquid and gas transmission networks, chemical pipelines, insulation projects, petroleum, district heating networks, central air conditioning ventilation ducts, municipal engineering, etc. Product Advantages: The steel pipe undergoes rust removal and anti-corrosion treatment; the polyurethane foam insulation layer provides excellent insulation, with a water temperature drop of less than 1°C per km when transporting 80°C hot water; the high-density polyethylene outer sheath is made of high-quality high-density polyethylene, possessing high mechanical strength, good weather resistance, and superior sealing performance, enabling long-term use in frozen soil and high-water-level geological conditions. Thermal insulation pipe production process On-site Construction of Anti-corrosion and Thermal Insulation Pipes Misalignment (Radial Misalignment) in Butt Welds: Ø Measure the pipe diameter or ellipticity to see if it exceeds the standard. Measure the pipe circumference and the diameter of the pipe ends. Ø If the pipe diameter or ellipticity does not exceed the standard, rotate one of the pipes to ensure welding, adjusting it to the optimal position where the two pipes are closest in size (radial misalignment between the two sections should not exceed 3mm) before welding. Residual Magnetism at Pipe Ends: When the residual magnetic induction intensity of the steel pipe is less than 40x10⁻⁴T, it has little impact on the welding operation; when the residual magnetic induction intensity is greater than 40x10⁻⁴T, it will affect the welding operation and welding quality. Methods for Measuring Residual Magnetism at Pipe Ends: Ø Use an angle grinder to grind the inner end wall of the steel pipe, grinding counterclockwise once to eliminate residual magnetism. Ø Coil Demagnetization: By conducting experiments, change the magnetic field to reduce magnetism.
