Steel pipeline anti-corrosion materials are divided into steel pipeline-themed anti-corrosion materials and their corresponding patching materials. The main body anti-corrosion mainly includes petroleum asphalt, epoxy coal asphalt, anti-corrosion cold-wound tape, epoxy powder, PE coating, and PP coating.
Commonly used patching methods include petroleum asphalt patching, epoxy coal pitch patching, anti-corrosion cold-wrapped tape, epoxy powder patching, and PE heat shrink material patching.
If the main body of the pipe is a three-layer PE composite structure, its patching material must be three layers of PE heat shrink patching material.
The single-layer epoxy powder coating can be patched in three ways: epoxy powder, primer + anti-corrosion cold-wrapped tape, and PE heat shrink patching.
In addition: the anti-corrosion layers of steel pipelines that are widely used in China include petroleum asphalt, PE jacket and PE foam jacket, epoxy coal pitch, coal tar enamel, epoxy powder three-layer composite structure, etc. The two most widely used ones are currently The steel pipeline anti-corrosion method is a three-layer PE composite structure and a single layer of powder epoxy.
Petroleum asphalt has a wide range of raw materials and low prices. However, the working conditions are poor, quality is difficult to guarantee, and environmental pollution is serious.
Epoxy coal pitch is easy to operate, but the covering layer takes a long time to cure and is greatly affected by the environment. It is not suitable for field operations and is difficult to construct below 10°C.
Anti-corrosion cold-wrapped tape is easy to operate, adaptable to on-site construction, has high waterproof performance, and good strength, and is not greatly affected by the environment.
Epoxy powder anti-corrosion uses electrostatic spraying. It fuses well with the anti-corrosion pipe body of the same material and has strong adhesion. However, the epoxy powder has poor waterproofing (water absorption rate is high, reaching 0.83%), which is not suitable for cathodic protection design. bring certain difficulties. On-site equipment requirements are high, operation is difficult, and quality is difficult to control.
3PE heat shrink material has strong anti-corrosion and sealing properties for steel pipelines, high mechanical strength, strong waterproofing, stable quality, convenient construction, good applicability, and does not pollute the environment. PE has low water absorption (less than 0.01%), high epoxy strength, low PE water absorption, and good hot melt adhesive softness, etc. It has high anti-corrosion reliability. The disadvantage is that compared with the cost of other repairing materials, costly.
The characteristics of anti-corrosion cold-wrapped tape and 3PE heat shrink tape are: they are suitable for main anti-corrosion layer pipes of various materials, while other methods are suitable for main anti-corrosion layer pipes of the same or close materials.
Secondly, with the development, some steel pipelines also need to be insulated during anti-corrosion. Petroleum is a very complex mixture that easily corrodes steel pipelines. Anti-corrosion is necessary. However, product oil steel pipelines also need to be insulated during anti-corrosion. In the Northeast and winter, Thermal expansion and contraction will cause pipes to freeze and crack, affecting stable supply.
Post time: Feb-02-2024