HJ Series of Tricone Bit The bit bearing can be ball locked, bit with ball lock bearing can be adapts to high rotary speed drilling well, safe and reliable. A pairs of metal face sealed was optimized, The two dynamic axial sealing rings of the sealing system are metal sealing, and two highly elastic rubber energizers are seated separately in head and cone sealing areas functioning as static seals. Optimized sealing compression assures good contact between the two metal sealing faces at all times. Reduce the friction heat and friction force. HJ series bits can be adapts to high rotary speed drilling well. All adapts different distance row tooth, compact numbers and the exposure height, rows was optimized. insert offset crested scoop compacts in soft formation. Journal bearing. Hard faced head bearing surface. Cone bearing inlaid with friction reducing alloy and then silver-plated. The load capacity and seizure resistance of the bearing is effectively improved. O rubber sealing ring is made of the more wear resistance high saturated buna-N the compression capacity of sealing was optimized, large section diameter rubber sealing ring, special sealing groove shape increased the reliability of the rubber sealing ring.

Bit size	Inch (in)	7 7/8	8 3/8	8 1/2	8 3/4	9 1/2	9 5/8	9 3/4	9 7/8	12 1/4	13 3/4
	Metric (mm)	212.7	212.7	215.9	222.2	241.3	244.5	247.3	250.8	311.1	349.2
Bit  type		447	417	417	417	417	517	517	417	417	417
		517	437	437	437	437	537	537	437	437	437
		537	517	517	517	517			517	517	517
		547	537	537	537	537			537	537
		617	617	617		617				617
			637	637		637				637
API Regular Pin (in)		4 1/2				6 5/8
Recommended make-up torque for bit shank(KN.m)		16.30-21.70				37.93-43.30