How to Divide the Fire Prevention Grade of Polyurethane Rubber Sheet
First, what is polyurethane rubber sheet?Polyurethane rubber sheet is a kind of polyurethane sandwich board made entirely of PU or composite of PU and color steel plate. It is mainly used in industrial and civil building external thermal insulation system and has become the most widely used product system of PU. Polyurethane rubber sheet has excellent thermal insulation performance, and its ideal bending resistance, sound insulation, fire resistance, high strength, flat surface, novel layout and other characteristics, which all reduce the thickness of the enclosure to a certain extent, and increase the net space of the building.
Second, how to divide the fire prevention grade of polyurethane rubber sheetIf we say that the fire prevention grade of polyurethane rubber sheet is divided into three kinds, someone will certainly ask which kind of fire prevention grade is higher? What are the differences among the three kinds of fire prevention grades?
Generally speaking, B1 grade polyurethane rubber sheet is the best fire protection grade, followed by B2, and B3 is the last. Polyurethane fireproof rubber sheet generally refers to polyurethane rubber sheet (B1 level) or polyurethane edge-sealing rock wool sandwich board (commonly known as A level in the market). In the process of engineering use, polyurethane fire-proof rubber sheet (pure polyurethane board) is the most commonly used level B2, but individual customers will also use level B3 polyurethane fire-proof board (polyurethane rubber sheet) due to project cost budget.
The division of fire protection grade is usually determined by the size of oxygen index. The oxygen index of the core material of grade B1 fireproof board must be greater than or equal to 32 during combustion test, while the oxygen index of the core material of grade B2 fireproof board must be greater than or equal to 26 during combustion test, and the oxygen index below 26 should be regarded as grade B3 plate. In the absence of professional instruments, there is also a simple way to test the fire resistance of the core material. Take a small piece of core material, ignite it with a lighter, leaving the fire without extinguishing and dropping the burner is grade B3, while leaving the fire without extinguishing is grade B2, and the board which is not easy to ignite is grade B1.