Drilling Rod: made by CNC, and multi-heat treat, with premium alloy steel BQ, ... Equipment ltd., is the professional manufacturer of drilling tool in china, and specializing in the design and ... head assembly and parts3.AQ-PQ, BTW, NTW, HTW, T2, T6 etc. Diamond core bit, reaming shell & shoe ... bit (syntheyic and surface-set, PDC) 4.Drill tool: hoisting plug, water swivel, overshot, outer tube & inner ...