As the proportion of plastic piping in hot and cold water supply and industrial piping engineering applications continues to increase, the quality control of plastic valves in plastic piping systems is becoming more and more important.
Due to the advantages of light weight, corrosion resistance, non-adsorption of scale, integrated connection with plastic pipes, and long service life of plastic valves, plastic valves are used in water supply (especially hot water and heating) and other industrial fluids. In the piping system, its application advantages are unmatched by other valves. At present, in the production and application of domestic plastic valves, there is no reliable method to control them, resulting in uneven quality of plastic valves for water supply and other fluids for industrial use, causing lax closure and leakage in engineering applications. Seriously, it has formed a statement that plastic valves cannot be used, which affects the overall development of plastic pipe applications. my country’s national standards for plastic valves are in the process of being formulated, and their product standards and method standards are formulated in accordance with international standards.
Internationally, the types of plastic valves mainly include MF BALL VALVE, butterfly valve, check valves, diaphragm valves, gate valves and Shut-off valve. The main structural forms are two-way, three-way and multi-way valves. The raw materials are mainly ABS, PVC-U, PVC- C, PB, PE, PP and PVDF etc.
In the international standards for plastic valve products, the first is to require the raw materials used in the production of valves. The manufacturer of the raw materials must have a creep failure curve that meets the standards of plastic piping products [1]; at the same time, the sealing test and valve body of plastic valves are required. The test, the long-term performance test of the integral valve, the fatigue strength test and the operating torque are all stipulated, and the design service life of the plastic valve used for industrial transportation of fluid is 25 years.
Post time: Sep-22-2021