... ) iso 9001:2008 4) SS304, SS304L,SS316,SS316L,carbon steel. Metal Pall Ring is made of material like carbon steel, stainless ... it is widely used in packing towers in petrochemical industry, chemical fertilizer industry and environmental protection, etc.Geometric ParametersSizes(mm)Bulk density ... : carbon steel, stainless steel including 304, 304L, 410,316, 316L. Metal Pall Ring