... carbide is fired by vacuum 2. high grade alloy steel and tungsten carbide tip 3.coal pick cutterHigh quality Mining bits ... rate, a long service life and short tool changing time. We can supply all kinds of bits in mining and construction, tunneling, steel, forestry ... /CSupply ability50,000 PCS/MonthDelivery time4~8 weeks Coal pick in all sizes,exporting grade coal mining pick,coal cutting picks