Research Article

A Computing Method for Sand Inrush Quantity through a Borehole in Longde Coal Mine

Table 6

Max roughness of technical standard in part country.

CountryMax roughness of technical standard (mm)Technical standard

China0.4GB1031-83
USA0.1BS1134-61/ASAB46.1-62
Switzerland0.2VSM10321-62
Italy0.1UNI13963-60
Japan0.4JISB0601-70
Poland0. 32PN58/M042-51