Polyurethane board refers to the polyurethane sandwich board made of PU, or formed by PU and color steel plate composite, mainly used in industrial and civil building insulation system, has become a widely used PU product system.
At present, the midline butterfly valve, as a part used to realize the on-off and flow control of pipeline system, has been widely used in many fields such as petroleum, chemical, metallurgy, hydropower and so on.