Epoxy powder anticorrosive steel pipes exhibit remarkable corrosion resistance, leading to their widespread application across various sectors of people's production, work, and daily life.
Epoxy resin, a common preservative, is utilized in the production of epoxy powder anticorrosive spiral steel pipes. These pipes boast rapid curing speed, short curing time, and high coating efficiency, with the entire production process streamlined through a conveyor line. The coating can be applied in a single layer using electrostatic spraying technology. The epoxy powder anticorrosive spiral steel pipes demonstrate excellent acid and alkali resistance, enabling them to function normally within a wide temperature range. Additionally, this coating is environmentally friendly, impact-resistant, heat-resistant, and possesses good bending properties.
These pipes find extensive applications in sectors such as oil, chemicals, natural gas, heating, sewage treatment, drinking water supply, marine facilities, construction, and mining.
Corrosion refers to the chemical and electrochemical effects of metallic materials and environmental media on metal surfaces, resulting in material degradation and damage. Common pipeline corrosion is primarily caused by corrosive substances like dissolved carbon dioxide, H2S, Cl-, trace dissolved oxygen, and bacteria, which directly interact with metals to initiate chemical corrosion.
The 3PE anticorrosive steel pipe manufacturing process begins with the application of an epoxy primer on the steel pipe surface. Subsequently, the pipe is fed into the coating zone at a specific rotational speed, where a layer of adhesive film with a certain thickness and density is extruded and wrapped around the pipe surface. While the adhesive is still molten, a second extruder extrudes a polyethylene film, which is wrapped around the adhesive to form the coating.
The three-layer polyethylene anticorrosive coating comprises an FBE (Fusion Bonded Epoxy) bottom layer with a thickness of approximately 50 to 128 microns, a copolymer adhesive middle layer of around 200 microns, and an outer polyethylene layer of approximately 3 millimeters. This structure combines the high adhesion, oxygen resistance, chemical corrosion resistance, and cathodic disbondment resistance of FBE with the moisture resistance, electrical insulation, and mechanical damage resistance of high-density polyethylene into a perfect organic whole. It features strong adhesion to the pipe surface, excellent electrical insulation, impact resistance, long service life, and low cathodic protection current density, which is merely 1 to 38A/m2.
From a long-term perspective, its superior cost-performance ratio is evident. The 3PE anticorrosive steel pipe structure comprises an epoxy powder layer (FBE > 100um) as the first layer, an adhesive layer (copolymer adhesive) of 170 to 250um as the second layer, and a polyethylene (PE) layer of 2.5 to 3.7mm as the third layer. These three materials are tightly fused together and bonded to the steel pipe, forming a thin pipe wall. Preheating is conducted according to the epoxy powder process. When the powder comes into contact with the pipe wall, it melts and adheres to it. Subsequently, suction is utilized to lower the temperature inside the pipe, reducing the amount of powder adhering to the pipe wall.
