The depth of cut (w)is the thickness of metal removed from the bar,measured in a radial direction. The product of these three gives the rate of metal removal,a parameter often used in measuring the efficiency of a cutting operation. V fw=rate of metal removal
The depth of cut (w) is the thickness of metal removed from the bar, measured in a radial direction. The product of these three gives the rate of metal removal, a parameter often used in measuring the efficiency of a cutting operation. V f w = rate of metal removal
Facing (车端面) Facing,also carried out on a lathe generates a flat surface,normal to the axis of rotation,by feeding the tool from the surface towards the center or outwards from the center. A characteristic of this operation is that the cutting speed varies continuously, approaching zero towards the center of Figure 13-28.Toolholders.A-Straight,left-hand,and right- the bar hand toolholders.(J.H.Williams and Co.)B-A turret-type tool- holder with four cutter bits.(ENCO Mfg.Co.)
Facing (车端面） Facing, also carried out on a lathe generates a flat surface, normal to the axis of rotation, by feeding the tool from the surface towards the center or outwards from the center. A characteristic of this operation is that the cutting speed varies continuously, approaching zero towards the center of the bar
Boring (镗削) Boring is to machine the internal cylinder surface of a work. Figure 15-1.Boring or machining internal surfaces is some-
Boring （镗削） Boring is to machine the internal cylinder surface of a work
Essentially the conditions of boring differ little from those of turning,but this operation illustrates the importance of rigidity in machining
Essentially the conditions of boring differ little from those of turning, but this operation illustrates the importance of rigidity in machining
Particularly when a long cylinder with a small internal diameter is bored,the bar holding the tool must be long and slender and cannot be as rigid as the thick, stocky(短而粗的)tools and tool post used for most turning
Particularly when a long cylinder with a small internal diameter is bored, the bar ( 刀 杆） holding the tool must be long and slender and cannot be as rigid as the thick, stocky（短而粗的） tools and tool post used for most turning