Polyethylene, due to its favorable mechanical and chemical characteristics, has been used for several decades for anti-corrosion protection of underground and underwater pipelines for the transport of gas, oil or water. To be resistant to heat and UV, it is stabilized with antioxidants and most often with carbon black.
The polyethylene coating is designed for operating temperatures up to 50˚C using low-density polyethylene (LDPE) and up to 70˚C for medium-density polyethylene (MDPE) and high-density polyethylene (HDPE). Increasing the density also improves the mechanical properties of the polyethylene.
Preparation of the pipe surface is performed by sandblasting to a degree of Ca 2 ½ with steel shot and angular steel granulate.
The coating consists of two layers:
- a layer of adhesive applied electrostatically to a heated tube at about 180˚C
- a layer of polyethylene applied by extrusion into a hose
Outer pipe diameter (D): from 88.9mm to 813mm
Coating manufacturing standard: DIN 30670, HF49704, EN10288
Types of coating:
- Nn, Nv, Sn, and Sv(DIN 30670);
- class 1, class 2 and class 3(HF 49704)
100% porosity test – test voltage 25KV
Uninsulated ends: 130mm to 150mm
Protective caps or steel rings – upon request from the customer
pipe length: 6m to 12.2m
Each pipe is marked with a text containing the trademark and company name, dimensions and quality of material and standard according to which the pipe is made, as well as the type and standard for the production of the outer coating. In the case when the pipes are packed in packages (diameter less than 219mm), the marking text is on a label attached to each package.
