Tungsten carbide inserts (TCI) bits available in the following types (series):

• N – the standard bit with open journal for various types of drilling;
• NE – the improved bit with open journal, tungsten carbide inserts on the gauge for various types of drilling;
• NS – the standard bit with sealed journal characterized by reliable lubrication of the bearing support for the responsible types of drilling;
• NSE – the improved standard bit with sealed journal characterized by increased rotation resource and improved wear resistance and improved cutting structure and bit stabilization for extremely difficult types of drilling;
• NA – the standard bit with air cleaning for different types of drilling operations in the direct air circulation;
• NAR – the standard bit with air cleaning for different types of drilling operations in the reverse air circulation;
• NAS – the standard bit with air cleaning characterized reliable lubrication of the sealed bearing and increased rotation resource for various types of drilling operations in the direct air circulation.

The cutting structure of cones corresponds to the IADC (International Association of Drilling Contractors) classification of roller rock bits by the first two digits of the IADC code in bit designation.

Design feature of bits:

• T – the additional tungsten carbide insert on heel rows;
• W – the tungsten carbide coating on cone bodies;
• D – the diamond coated tungsten carbide inserts on the gauge of the cones;
• P – the leg pad;
• G – tungsten carbide inserts on the shirttail of the legs;
• C – the additional central nozzle for cleaning cones.

Examples of designation to bits:

165,1 NA73 — standard TCI bit with air circulation and IADC 732;

215,9 NS51GC — standard TCI bits with sealed bearings and IADC 517 having carbide inserts on the shirttail of the legs and an additional central nozzle;

215,9 NSE51DGPC — improved TCI bits with sealed bearings and IADC 517 having diamond coated tungsten carbide inserts on the gauge of cones, tungsten carbide inserts on the shirttail of the legs, leg pads and additional central nozzle.