Machine Tools Matching : Practice Questions and Answers

As per the working of the upmilling, at the begining the the thickness of chip is minimum as cutting force vary from zero to maximum in upmilling. So intially thickness of chip is minimum.

Down milling is also known as climb milling as in this process metal is removed by cutter which rotates in the same direction of the travel of the work piece.

Up milling is also known as conventional milling as in this process metal is removed by cutter which rotates in the opposite direction of the travel of the work piece.

Peripheral milling is the type of milling in which produced machine surface remains parallel to the axis of cutter.

Various milling process may be classified in 2 categories: peripheral milling and face milling.

High speed steel has some advanced quality and so it is very accurate even on small diameters. So it is easy to grind high speed steel. Again, this high speed steel is generally used for intermittent cut.

The answer should be none of mentioned. This is the quality of carbon steel.

Carbides are used for these both reasons. But they are not used for comparatively small jobs.

Machine tools must be tough enough to withstand these both in order to provide stability against downward pressure and to perform the job more accurately.

Ceramics are used for this purpose. They are not suitable for intermittent cut and even for small diameters.

Ceramic has poor shock resistant. Apart from this, it has high wear resistance and again has very high stock removal rate.

It has excessive wear on casting and hard materials and that’s why can only perform slow and medium cutting speeds.

For ceramics, we need rigid machines. The other two mentioned disadvantages are true for diamond.

Stellites cannot be forged to shape easily because they are very brittle in nature.

Carbides are not suitable for small diameters as these carbides has higher speeds and generally used in rapid stock removal.

An electric motor rotates at constant speed in crank and slotted mechanism. As the crank rotates, the slotted link also oscillates. Here slotted link means lever.

These both desired properties are obtained in all mentioned mechanisms. These are desired properties which is needed for any mechanism to perform more accurately and better.

In return stroke no useful work is done so to reduce cutting time it is advisable to complete the return stroke as fast as possible.

It is the desired property for standard shaper because only in forward stroke the useful work is done. So it should be slower than return stroke.

The metal is removed in forward stroke because only in forward stroke the useful work is done.