... is good.(3)Long work life.(4)Stocks adequate, time delivery.(5)Rich experience in drill bit.(6)High ... /2", 9 1/2", 9 5/8", 11 5/8", 12 1/4", 13 5/8", 14 3/4", 15 ... sealed journal bearing)Aircooled bearing typeapplicationPetroleum and gas, water well, mining and tectonic industries, oil field, construction ... better performance when PDC used in the drilling bits.3.Nearly all of our PDC cutters are designed ...