Tungsten solid carbide center drills prefabricated hole machining for precise positioning, guide twist conduct drilling, reduce errors, is the center of the end surface of hole machining for parts such as shafts. Tungsten solid carbide center drills cutting brisk, chip well. There are two kinds of types:
A-type : center without protecting cone drill
B-type : center with guard cone drill
When the machining diameter of the center hole d = 1 ~ 10mm, and usually without the protective cone center drill (A-type); higher step is longer, the accuracy requirements of the workpiece, the centering cone of 60 degrees in order to avoid being damaged, with the general care center cone cone (B-type).
Center drill classification: p>
Center hole is positioned based on the top surface of the workpiece shaft installed. 60 ° 60 ° taper cone with the top center hole on the fit; small hole in the side, in order to ensure top cone with tapered bore and appropriate, and can store a small amount of lubricating oil (butter). Center hole common with A and B type. A type center hole only 60 ° taper. B-type center hole of the outer end of the 120 ° cone, also known as protective cone, 60 ° cone to protect the outer edge of the hole without being damaged. A-type and B-type center hole, respectively, with the corresponding center drill on a lathe or a dedicated machining. Preceded machining center hole of the end face of the horizontal axis of the car to prevent the center drill break, standard center drill peak angle is generally 118 degrees.
Variety of tungsten solid carbide center drills dimensions (unit: mm):