Center Drill and Hot Melt Drill

Center drill is a common tool in machining, which plays an important role in actual production.  

Center drill used in the earliest lathes, is used to play shaft parts of the center hole.  With the increasing prevalence of automation, it should be more widely used in multifunctional CNC equipment.  Its biggest function is the point center hole, in order to ensure the parts of the hole processing position. 

The center hole is the positioning base surface on which the shaft workpiece is mounted on the center.  The 60° cone hole of the center hole is matched with the 60° cone surface of the center hole; The small round hole in the inner end, in order to ensure that the cone hole and the top cone fit properly, and can store a small amount of lubricating oil (butter).  

The common center holes are type A and type B.  Type A center hole has only a 60° cone hole.  The 120° cone surface of the outer end of the B type center hole is also called the protection cone surface, which is used to protect the outer edge of the 60° cone hole from being damaged.  Type A and type B center holes, respectively, with the corresponding center drill on the lathe or special machine tool processing.  The end face of the shaft should be flattened before the machining center hole to prevent the center drill from breaking, and the peak Angle of the standard center drill is generally 118 degrees.