The physics and mechanical properties of the oily conveyer belt covedng layer rubber are as mentioned in the following table: Typebreak the intensity /mpabreak extension rate /%wearing and tearing /mm3 Lo14.0350200 Do16.0350160 Notes: Lo--oily conveyer belt under the general condition; Do--conveyer belt under the shock resistant and oily condition. Oil proof performance of the oil proof conveyer belt covering layer is as mentioned in the following table: Serial numberexperimental condition in soaking the liquidmrate of change of the volume /% Oil number in gb/t1690soaking temperature /soaking time /hlodo 1oil no.270±270ï0/ 1+20-5 2oil no.370±270ï0/ 1+50+5 3oil no.3100±222±0.25+50+5 Notes:one of oil proof testing is ok.