The center hole is the guarantee Shaft partsMachining accuracy of the benchmark hole, according to the national standardGBone145one1985Stipulate that the center hole can be dividedAType center hole,BType center hole,CType center hole as wellRType center hole, next, by the billion Red for you to briefly introduce this4Plant the center hole.
    (1)ACenter hole
    AThe type center hole is also known as the center hole without the guard cone, which only contains60°A cone hole. This center hole is only used in rough machining or do not require the retention of the center hole on the workpiece, its diameterdandDMainly according to the diameter and quality of the shaft workpiece to determine.

    AThe main disadvantage of the center hole is that the hole is easy to be damaged, resulting in poor contact between the center hole and the top cone, which causes the runout of the workpiece and affects the accuracy of the workpiece.

    (2)BCenter hole
    BType center hole is also known as the center hole with protection cone, which60°And the outer end of the cone hole120°The protective cone to protect60°The outer edge of the cone hole is not damaged or destroyed.

    BThe center hole is mainly used for the case that the center hole should continue to be used after the parts are processed, such as the center hole on the tool such as the reamer.

    (3)CCenter hole

    CThe main feature of the center hole is that there is a small section of threaded holes on it, as shown in the figure. It is used when the workpiece is required to be fixed on the shaft, such as the center hole above the taper shank end mill used on the milling machine, the taper shank keyway mill and its connecting sleeveCType center hole.

    (4)RCenter hole

    RType center hole is also called circular arc center hole, because of its connection with60°The contact of the top, theoretically speaking, is line contact, so the friction generated when the center and the center hole are relatively rotating is small, the rotation is light, and the processing accuracy of the center hole is high. Therefore, the positioning accuracy requirements are moreShaft partsAnd round broach and other precision tools, should be selectedRType center hole.

    Eileride specializes in pneumatic measurement of precision parts size, producing measuring tables that can quickly and accurately measure crankshaft length, inside and outside diameter, outside diameter roundness, outside diameter runout, cylindricity, concentricity and other dimensional parameters if you want Measuring the dimensions of shaft partsOr for more information, please click on our online customer service for consultation, or call the national unified service hotline directly 400-682-7787. We look forward to your call!