With asbestos cement mortar pipe being used as inner liner, concrete is cast to form hollow slab.
以石棉水泥砂浆离心管作为内模衬管，浇筑混凝土后构成现浇混凝土空心板。
2
Asbestos rubber sheet in which the structure of dense, good pressure, good heat resistance, and valves in the valve itself and the pipe flange connection, the use of a wide range.