Polyethylene coated anti-corrosion steel pipe

Polyethylene coated anti-corrosion steel pipe is a type of steel pipe that has undergone anti-corrosion treatment, in which polyethylene material is coated on the surface of the steel pipe to achieve anti-corrosion purposes. Common types include inner oxygen outer polyethylene anti-corrosion steel pipes and three-layer structure polyethylene (3PE) anti-corrosion steel pipes. Among them, the inner oxygen outer polyethylene anti-corrosion steel pipe is a composite pipeline composed of an inner layer of epoxy resin coating and an outer layer of polyethylene protective layer; The inner layer of 3PE anti-corrosion steel pipe is coated with epoxy powder, the middle layer is adhesive, and the outer layer is polyethylene.

Characteristics and advantages

Performance characteristics

Corrosion resistance: Polyethylene material itself has good corrosion resistance, which can effectively prevent various chemical substances from corroding steel pipes and extend the service life of pipelines. For example, the anti-corrosion layer of 3PE anti-corrosion steel pipes can be used for a long time in different harsh environments, and buried pipelines using 3PE anti-corrosion technology can last up to 50 years.

Wear resistance: It can withstand a certain degree of friction and wear, ensuring the integrity of the pipeline during use.

High pressure and high temperature resistance: It can adapt to working environments with high pressure and high temperature. For example, TPE material in TPEP anti-corrosion steel pipes can withstand high temperatures and maintain good performance in some special environments, without deformation or damage.

Good toughness and strength: Using metal pipes, the strength and hardness are much better than plastic pipes, and it has good toughness, can withstand certain pressure and impact forces, and can adapt to the anti-corrosion requirements of pipelines in various complex environments.

Other advantages

Smooth inner wall: low transmission resistance, no scaling, conducive to fluid transportation.

Diverse connection methods: easy to construct, able to meet the installation needs of different projects.

Reasonable price: Low overall cost, with good economy while maintaining performance.

Environmental protection: TPE materials do not release harmful substances during production and use, meet the hygiene standards for drinking water, and ensure safe water quality.

application area 

Oil and natural gas transportation: 3PE anti-corrosion steel pipes are widely used in long-distance pipeline engineering for oil and natural gas transportation. Their excellent anti-corrosion and mechanical properties can ensure the safe transportation of oil and gas.

Urban centralized water supply project: The environmental friendliness and corrosion resistance of polyethylene coated anti-corrosion steel pipes make them suitable for urban centralized water supply, with pollution-free water quality and long pipeline usage time.

Other fields: It is also widely used for buried pipelines, water transmission pipelines, drainage pipelines, reservoir water diversion, factory discharge, and other purposes.

Manufacturing and construction related

manufacturing process

For 3PE anti-corrosion steel pipes, the process is an anti-corrosion technology introduced from abroad in the late 1990s, fully known as fusion bonded epoxy/extruded polyethylene structural protective layer, which combines the excellent performance of epoxy coating and extruded polyethylene anti-corrosion layer.

TPEP anti-corrosion steel pipe is an upgraded product based on the fusion bonded epoxy composite steel pipe with outer polyethylene. The outer wall adopts the hot-melt bonding and winding process, and the bottom layer of epoxy resin, the middle layer of adhesive, and the outer layer of polyethylene form a three-layer structure of anti-corrosion layer. The inner wall adopts the thermal spraying epoxy powder anti-corrosion method, and the powder is uniformly coated on the surface of the pipe after high-temperature heating and fusion.

Construction precautions

Taking buried steel pipelines with polyethylene anti-corrosion coatings as an example, it is important to choose the correct type during construction, and the surface treatment of the substrate and construction process should meet their respective requirements. When painting, attention should be paid to the surface condition and atmospheric environment. Construction should not be carried out under low temperature conditions below zero degrees Celsius, and solvents evaporate quickly at high temperatures. After opening the bucket, it should be used up as soon as possible. During the construction period, a mixer should be used to continuously mix and seal with primer. Before applying the next coat, the previous paint film needs to be completely cured, and the construction site requires good ventilation.