Lathe center

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Center
표준형 center live center pipe용 bevel center half center	parts of a live center The rotating spindle is extended right through the tapered shank. Two specially designed adjustable needle-roller bearings carry all radial loads. A heavy duty ball thrust bearing takes all axial thrust. Complete protection of bearings form the ingress of coolant, dirt or swarf is provided by the built-in oil-seal, which also prevents loss of lubricant.
A dead center(one that does not turn freely, ie:- dead) may be used to support the workpiece at either the fixed or rotating end of the machine. When used in the fixed position, a dead center produces friction between the workpiece and center, due to the rotation of the workpiece. Lubrication is therefore required between the center and workpiece to prevent friction welding from occurring. Additionally the tip of the center may have an insert of carbide which will reduce the friction slightly and allow for faster speeds. Dead centers may also be fully hardened to prevent damage to the important mating surfaces taper of the taper and to preserve the 60 ° nose taper. A live center or revolving center is constructed so that the 60 ° center runs in its own bearings and is used at the non driven or tailstock end of a machine.[1] It allows higher turning speeds without the need for separate lubrication, and also greater clamping pressures. CNC lathes use this type of center almost exclusively and they may be used for general machining operations as well. The term live center may also refer to a dead center when mounted in the spindle of the machine, where it is considered to be live by virtue of the spindle bearings rather than its own bearings.[ A pipe center has a larger diameter at the 60 ° taper end. This allows the center to be used in the bore of a pipe (or similar workpiece). While a pipe center ensures the workpiece remains concentric, its main advatage is that it supports the workpiece securely. Thin walled material such as pipes easily collapse if excessive pressures are used at the chuck end,

4 편 기 계 가 공

Center

표준형 center

live center

pipe용 bevel center

half center

parts of a live center

The rotating spindle is extended right through the tapered shank.
Two specially designed adjustable needle-roller bearings carry all radial loads.
A heavy duty ball thrust bearing takes all axial thrust.
Complete protection of bearings form the ingress of coolant, dirt or swarf is provided by the built-in oil-seal, which also prevents loss of lubricant.

A dead center(one that does not turn freely, ie:- dead) may be used to support the workpiece at either the fixed or rotating end of the machine. When used in the fixed position, a dead center produces friction between the workpiece and center, due to the rotation of the workpiece. Lubrication is therefore required between the center and workpiece to prevent friction welding from occurring. Additionally the tip of the center may have an insert of carbide which will reduce the friction slightly and allow for faster speeds. Dead centers may also be fully hardened to prevent damage to the important mating surfaces taper of the taper and to preserve the 60 ° nose taper.

A live center or revolving center is constructed so that the 60 ° center runs in its own bearings and is used at the non driven or tailstock end of a machine.[1] It allows higher turning speeds without the need for separate lubrication, and also greater clamping pressures. CNC lathes use this type of center almost exclusively and they may be used for general machining operations as well.
The term live center may also refer to a dead center when mounted in the spindle of the machine, where it is considered to be live by virtue of the spindle bearings rather than its own bearings.[

A pipe center has a larger diameter at the 60 ° taper end. This allows the center to be used in the bore of a pipe (or similar workpiece). While a pipe center ensures the workpiece remains concentric, its main advatage is that it supports the workpiece securely. Thin walled material such as pipes easily collapse if excessive pressures are used at the chuck end,