“TEPP” E series roller cone bit is developed on the basis of Kingdream FJ series product, and it is such a new series bit that combines special T and S features as well as head OD active gage protection and side cutting technologies. It is suitable for high RPM and high WOB drilling applications and features long service life, and is the ideal tool for drilling directional wells, horizontal wells and high temperature deep wells.
Main Structure Features:
- Floating bearing structure. The floating elements are made of new materials with high strength, high elasticity, high wear resistance and can endure high temperature, and bearing surface is treated with solid lubricant. This decreases the relative linear velocity of the bearing couple and reduces the temperature of the friction surfaces, which result in improved reliability and working life of the bearing under large WOB and high RPM conditions.
- Precise metal face sealed. The two dynamic axial sealing rings of the sealing system are metal seals, and two highly elastic rubber energizers are seated separately in head and cone sealing areas functioning as static seals. Optimized sealing compression ensures good contact between the two metal sealing faces at all times.
- Ball locked cone, suitable for high rotary speed.
- 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.
- New type of wear resistant grease that can sustain high temperature up to 250°C is utilized.
- Advanced secondary cutter technology (i.e. special S structure feature) is used, which solved the problem of low bottom hole coverage coefficient normally found with conventional insert bit and effectively increased cutting ability of the bit and wear resistance of the cone shell.
- Friction force and friction heat generated on the base of cone gage due to contacting with borehole wall while the bit is working is reduced by having gage compacts exposed to a certain height, and working life of the bearing seal is consequently extended.
- In equable spaced compacts arrangement, and optimized number of rows, number of compacts and compact exposure. Offset crested scoop compacts are used for drilling soft formations.
- Carbide compacts are fitted with certain exposure on side of the bit head and trimmers are equipped on cone (i.e. special T structure feature) so that side cutting ability of the bit is greatly improved and perfect well bore quality can be ensured.