QSY XQ9 PE combined with epoxy resin and polyethylene anti-corrosion steel pipe

Technical standard for QSY XQ9 anti-corrosion steel pipe

QSY XQ9 is an important technical standard for dissolving epoxy powder external anti-corrosion coatings on steel pipelines. This standard specifies the material properties, construction processes, and testing requirements for epoxy powder coatings. The core process includes surface pretreatment of steel pipes, electrostatic spraying of epoxy powder, and high-temperature curing. The coating has high adhesion and corrosion resistance to the metal substrate. This standard, together with technical specifications such as SY/T0447-96, constitutes the quality control system for epoxy powder anti-corrosion steel pipes, suitable for the anti-corrosion requirements of high-pressure transmission pipelines such as oil and natural gas.

Structural characteristics of QSY XQ9 anti-corrosion steel pipe

Anti corrosion steel pipes that comply with QSY XQ9 standards typically use a composite structure of fusion bonded epoxy powder (FBE) and polyethylene (PE) to form a three-layer protective system (3PE). The bottom layer is coated with epoxy powder, providing excellent chemical inertness and adhesion; The middle layer is a copolymer adhesive, which enhances the interlayer bonding force; The outer layer is a polyethylene protective layer, which resists mechanical damage and ultraviolet radiation. This multi-layer composite structure significantly improves the corrosion resistance, impact resistance, and service life of pipelines, especially suitable for harsh environments such as buried or underwater.

Application fields of QSY XQ9 anti-corrosion steel pipe

This type of steel pipe is widely used in long-distance oil and gas pipelines, urban gas pipelines, chemical medium transportation, and municipal water supply and drainage engineering. For example, in high-pressure oil and gas transportation, its high temperature resistance (up to 115 ℃) and resistance to cathodic stripping ensure the long-term stability of the pipeline; In municipal engineering, the food grade safety of epoxy powder coating makes it suitable for transporting drinking water. In addition, this standard product is also suitable for special environments such as offshore platforms and mine ventilation, meeting the anti-corrosion requirements in different scenarios.

Production process and quality control

The production of QSY XQ9 anti-corrosion steel pipes requires strict procedures: first, the surface of the steel pipe is sandblasted to achieve a Sa2.5 cleanliness level, then heated to the curing temperature of epoxy powder (about 230 ℃) through medium frequency heating, and then uniformly covered with epoxy powder and cured using electrostatic spraying technology. The key points of quality control include coating thickness (usually ≥ 300 μ m), pinhole detection (electric spark leak detection), and adhesion testing (grid method). Strengthening anti-corrosion measures will also increase the thickness of the polyethylene layer to over 3mm, further enhancing the protection level.

Comparative advantages with other anti-corrosion technologies

Compared to single-layer epoxy coating (FBE) or traditional asphalt anti-corrosion, the three-layer PE structure of QSY XQ9 standard combines the chemical stability of epoxy resin with the mechanical protection of polyethylene, and its resistance to soil stress and microbial erosion is significantly better than other processes. For example, in the same corrosive environment, the time for 3PE anti-corrosion steel pipes can be 3-5 times that of traditional technology, and the construction efficiency is higher. Through mechanized spraying, pipeline anti-corrosion treatment can be achieved for 1-2 kilometers per day.