Main structure features
1.Journal bearing. Hardfaced head bearing surface. Inner hole of cone is silver-plated. The load capacity and seizure resistance of the bearing is greatly improved.
O ring seal is made of the more wear resistance high saturated buna-N with the increased seal section and precisely designed sealing flange in the cone sealing area increased the reliability of the seal.
2.All rubber compensator is used which can limit pressure differential and prevent drilling fluid from entering the lubrication system and this provides the bearing system with good assurance of lubrication.
3.High wear resistance and excellent cutting ability of the insert bit are given full play by using carbide compacts of high
strength and high toughness in combination with optimized compact numbers and rows,the exposure height and special shaped compacts. For steel tooth bit the tooth surface is hardface with new type of wear resistant material and thus extended working life of the cutting structure while still maintaining high ROP.
4.A row of inserts is added between gauge row and heel row of HA bit to trim borehole wall and protect cone shell and
consequently,the special HAT series bit is formed.