Galvanized steel pipes are divided into cold-plated pipes and hot-plated pipes. The former has been banned, and the latter has been promoted temporarily by the state.
Hot dip galvanized pipe
The molten metal is reacted with an iron matrix to produce an alloy layer, thereby combining the substrate and the plating layer. Hot-dip galvanizing is to pickle the steel pipe first, in order to remove the iron oxide on the surface of the steel pipe, after pickling, it is washed by ammonium chloride or zinc chloride aqueous solution or a mixed aqueous solution of ammonium chloride and zinc chloride, and then fed. Hot dip plating tank. Hot-dip galvanizing has the advantages of uniform plating, strong adhesion and long service life.
Cold galvanized pipe
Cold galvanizing is electrogalvanizing. The amount of galvanizing is very small, only 10-50g/m2, and its corrosion resistance is much worse than that of hot-dip galvanized pipes. Regular galvanized pipe manufacturers, in order to ensure quality, most do not use electro-galvanizing (cold plating). Only small companies with small equipment and old equipment use electro-galvanized steel, of course, their prices are relatively cheaper. At present, the Ministry of Construction has officially laid down the cold-galvanized pipe with backward technology, and the cold-galvanized pipe is not allowed to be used as water and gas pipe in the future.
Hot dip galvanized steel
The steel pipe matrix and the molten plating solution undergo complex physical and chemical reactions to form a corrosion-resistant structure of a zinc-iron alloy layer. The alloy layer is integrated with the pure zinc layer and the steel pipe base. Therefore, its corrosion resistance is strong.
Cold galvanized steel pipe
The zinc layer is an electroplated layer, and the zinc layer and the steel pipe matrix are layered independently. The zinc layer is thin, and the zinc layer is simply attached to the steel pipe base and is easy to fall off. Therefore, its corrosion resistance is poor. In newly built houses, the use of cold-galvanized steel pipes as water supply pipes is prohibited.
PVC High Speed Door are designed for indoor use and ensure rapid handling operations between different areas that should remain separated. These safe and efficient industrial doors are made of a shaped steel frame and covered with PVC. These high speed doors are safe and efficient and consist of a shaped steel frame covered with PVC. Safety is ensured by their photocells and barriers.
High speed doors protect us from harm, save energy and help us to separate processes for optimal productivity. A high speed door's most important job is to simply open and close quickly and safely every time you need it.
The high speed pvc roll shutter door require high strains, caused by the high operating speed and the frequency of openings, have to be taken into account during construction. In the same way, basic conditions like size and installation location add up to considerable requirements regarding safety and control technique.
PVC High Speed Door,Large PVC High Speed Door,Transparent High Speed Door,Great Performance High Speed Door
Shenzhen Hongfa Automatic Door Co., Ltd. , https://www.pvchighspeeddoor.com