... equipment,HIP 4.Good service tungsten carbide balls in various of sizes * High strength, high wear resistance, high precision, high temperature ... , corrosion resistant. * They are mainly used for the sealing of valves of oil pumps in petroleum industry's sand containing wells, viscous ... could offer free samples below 0.5kgs under the condition of freight paid by customer;9/ MOQ 5kgs for sintered blank ...