petroleum fracturing proppant 1,Increase oil output of 30%-50% 2,AAcredit ... .. 2.specification now we maily produce 30/50,20/40,40/70,low ,medium,high density Sieve size Bulk densityg/cm3Specific ... stressMPa(KN)Crush resistance% 850~425(20/40)600~300(30/50)≤1.65≤3.0052(105)69(140)≤8. ... 0≤8.0≤1.80≤3.3552(105)69(140)86 (174)≤5 ... .0≤7.0≤9.0>1.80>3.3569 (140)86 (174)≤5.0≤9 ...