Fully-ground twist drill

At present, the world's most mainstream twist drill technology, twist drill from the beginning of the material to the grinding ditch, grinding back, cutting edge, opening Angle, are made of grinding wheel.

After fully polished twist drill appearance is beautiful and clean, radial circular runout, core thickness, core thickness increment and other key dimensions have been very well controlled, high precision.

However, in fact, as long as the rolling process and the level of heat treatment in place, from the point of view of durability or rolling is better, which is why the work of twist drill has been rolled.