... Tricone bit1.High-strength, high flexibility, high temperature, high wear resistance.2. High-precision metal seal.3. Locking roller ... carbide teeth,5. Hours in the rotary cone bit with the impact, crushing and shearing the role of ... the twenty years, we have built good business relationships with customers abroad, such as America, Japan, Korea, ... ,517,537,617,637 75mm opening bearing tricone bit