Why we need a tapered drill bit?Because the tapered drill bit drill things just contact point,after point drilling positioning, and then gradually is facet,through facet to the large, torque is increased, so the contact surface of the tapered drill bit is also increased, an increase of intensity of the tapered drill bit, so the bit is tapered and calmly drill cuttings, cone-shaped is also good.
1, the general use of the smallest diameter is four
2, mechanical woodwork drill comprises a drill, the circumferential cutting edge, the main cutting edge, flutes, main cutting edge of the knife surface cross-section shape or straight, or concave circular arc shape; the shape of the drill point or pyramid, or conical screw. After the main cutting edge, the alpha increases obviously, and the edge of the blade is sharp. When drilling, axial force is significantly reduced, increased feed rate, thus providing a work efficiency, reduces the labor intensity; at the same time, due to the increase of the main cutting edge of rear angle alpha, it reduced after blade surface and material of friction so that the tapered drill bit is not easy to generate heat, reduce the friction losses of the bit and prolong the service life of the drill bit.
The utility model relates to a conical spiral drill bit, which relates to a conical spiral rock bit, in particular to a drill bit which can be used for drilling and piling on the rock foundation. It includes cylindrical body and at the both ends of the cylindrical,its main body are respectively provided with even for one of the cone tip,connecting flange and cylindrical body and a connecting flange perpendicular to each other; in the cylindrical body and along the axial direction, symmetrically with even for one of the two conical helical blade, and conical spiral blade taper and taper tip taper direction consistent; on the cone tip apex, bottom, cone and cone type spiral leaf blade are inlaid with spacing of 1.5 to 2.5 cm of the hard alloy block.And the hard alloy blocks in the cone on the cone is spiral. Rock with less than 35MPa of hardness can be drilled directly.