The passivation process of large flange can be divided into wet process and dry process. It can be divided into many types. The passivation of large flange depends not only on the passivation process, but also on the material itself. The specific influencing factors include the elements contained in large flange, stainless steel metallographic structure, stainless steel processing state and so on. Among the constituent elements, chromium and nickel are the elements with strong passivation, followed by iron. Therefore, the higher the content of chromium and nickel, the stronger the passivation of stainless steel. Austenitic and ferritic large flange has more uniform structure and better passivation. Martensitic stainless steel is strengthened by heat treatment, and its metallographic structure is multiphase structure, so its passivation is not strong.
After machining, the smooth surface of large flange has good passivation, and the workpiece obtained by forging and sandblasting is rough and dry, which is bad for passivation.
Large flange material not only has a qualified creep rupture curve, but also its pipe price is moderate, reliable standard mutual melting hot-melt connection form. The diameter of pipe fitting is larger than the inner diameter of pipe of the same specification. Compared with other products, the construction is convenient and fast. The connection form belongs to the present stage. Due to the mechanical connection without local shrinkage in the system So the fluid resistance of the system is relatively small.
Large flange durable pressure function, only from the design stress, high pressure flange manufacturers large flange pressure function is good. However, due to various factors, the actual wall thickness of the floor heating pipe is only 2mm. Under this wall thickness, all kinds of pipes can meet the requirements of floor heating, and the pressure resistance advantage of large flange is easy to emerge;
Low temperature impact resistance of large flange: PE -- RT and PEX products have good low temperature impact resistance. In winter construction, the pipe is not easy to be impacted and split, which increases the agility of construction placement.
Large flange environmental protection: PE-RT can be recycled operation, does not pollute the environment. However, if PEX can not be recycled, secondary pollution will occur.