Newest Three cone bit 1)used for oil filed, water well 2)metal seal or rubber seal 3)used to drill ... with you and your company sincerely.HJ series bit for oil well drillingMain structure features: 1. High precision journal bearing with ... ,617,637 TypeTricone bits, Steel tooth bits, PDC bits Appliablewater well, oil field, construction, geothermal, directional boring, and underground foundation work ...