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■ Applicable formation: Class II, III and IV surrounding rocks, Natural Compressive Strength of Formation 80-120 Mpa, high compressive strength, medium-hard, thick hard interbeds, such as hard shale, limestone, sandstone, dolomite, gneiss, conglomerate, etc.
■ Product features: Cutting teeth are elongated conical spherical teeth, and the outer row is high strength spherical teeth. O-ring rubber seal, new bearing system, new grease storage compensation pressure balance system.
■ Recommended drilling pressure：200KN~350KN