Introduction to 3LPE anti-corrosion steel pipe

Definition and Structure

3LPE anti-corrosion steel pipe refers to a three-layer structure polyolefin coating (MAPEC) external anti-corrosion steel pipe, generally referring to the anti-corrosion of the outer wall of the steel pipe. It usually consists of a three-layer structure: the first layer is epoxy powder (FBE), the thickness of which is generally not explicitly mentioned; The second layer is adhesive (AD) with a thickness of 170-250 μ m; The third layer is polyethylene (PE) with a thickness of 2.5-3.7mm. In practical operation, these three materials are mixed and integrated into one, and after processing, they are firmly combined with steel pipes to form an excellent anti-corrosion layer.

Processing method

Its processing methods are generally divided into two types: winding and circular mold wrapping.

Coating characteristics

The 3LPE anti-corrosion steel pipe coating is a new anti-corrosion steel pipe coating that cleverly combines the European 2PE anti-corrosion layer with the widely used epoxy powder anti-corrosion steel pipe coating (FBE) in North America. It combines the high impermeability and mechanical properties of epoxy resin and polyethylene materials. The bottom layer contacts the steel pipe surface with an epoxy powder anti-corrosion coating, the middle layer is a copolymer adhesive with branched functional groups, and the surface layer is a high-density polyethylene anti-corrosion coating.

Type of base material

The base materials for 3LPE anti-corrosion steel pipes include seamless steel pipes, spiral steel pipes, and straight seam steel pipes.

advantage

1. Long service life: Ordinary steel pipes are prone to severe corrosion in harsh environments, reducing their service life, while 3LPE anti-corrosion and insulation steel pipes can generally be used for about 30-50 years. Proper installation and use can also reduce the cost of pipeline maintenance, and an alarm system can be set up to automatically detect pipeline leakage faults, accurately indicate the fault location, and automatically sound an alarm.

2. Good insulation performance: The heat loss is only 25% of traditional pipes, and long-term operation can save a lot of resources and significantly reduce energy costs.

3. Strong waterproof and corrosion-resistant ability: No need to attach pipe trenches, can be directly buried underground or in water, easy and fast construction, and low overall cost.

4. Good low-temperature performance: It has good corrosion resistance and impact resistance under low-temperature conditions, and can be directly buried in frozen soil in certain environments.

application area 

The three-layer polyethylene (3PE) anti-corrosion coating has been widely used in the petroleum pipeline industry due to its excellent corrosion resistance, water vapor permeability resistance, and mechanical properties. In addition, it can also be used for agricultural irrigation pipes, deep well pipes, drainage pipes and other networks, as well as in fields such as water conservancy engineering and gas transportation.

production process

Before carrying out anti-corrosion treatment on the base material, it is necessary to inspect and record the steel pipes entering the inlet platform, perform shot blasting and rust removal on the outer surface of the steel pipes, and then check whether the cleanliness and anchor depth of the outer surface of the steel pipes meet the requirements. If they do not meet the requirements, they should be polished and repaired with a hand grinding wheel. Afterwards, wrap the tube end with adhesive tape for dust treatment, heat it to the required temperature at medium frequency, spray epoxy powder, wrap it on the side of the adhesive extruder, wrap it on the side of the PE extruder, cool the anti-corrosion tube with water, spray label the qualified products, and finally lower the tube platform and stack it for shipment.

Finished product inspection

1. Appearance inspection: Check whether the surface of the anti-corrosion layer is smooth, free of bubbles, pockmarks, wrinkles, defects, etc.

2. Thickness inspection of anti-corrosion coating: When using a thickness gauge for testing, the gauge must be verified by the testing department. Two sections should be randomly inspected within every 100 meters of the pipeline, with two points above and below each section. If one of the points is not qualified, another four sections should be randomly inspected. If two of the points are still unqualified, the inspection section is considered unqualified.

3. Performance testing of anti-corrosion coating: mainly testing whether its chemical corrosiveness, wear resistance, adhesion and other properties meet the requirements.