... in geological prospecting, coal mining and oil well boring.YG814.80220089.5For coring crowns, electric coal drill bits, coal cutting picks, oil cone ... percussion bits and tricone bits to cut medium-hard, hard, and very hard formations.YG13C14.2285086.0Primarily for the buttons of ... high-purity Original/Virgin Raw Materials and HIP/Sintered, with very high quality and excellent performances. Also the ...