| Mechanical Definitions
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                | Quadrant : It is a device which is used to convert horizontal reciprocating motion to vertical reciprocating
				  motion.
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                | Quarrying Machine : It is a machine which is designed for drilling holes or cutting tunnels in native rock, a
				  gang drill or tunneling machine for example. Usually it is a small locomotive bearing rock drilling equipment which is
				  operating on a track.
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                | Quarter-turn drive : It is a belt drive which is used for connecting pulleys whose axes are at right angles.
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                | Quenching : It is the process of dipping of heated steel into water, oil or other bath in order to impart
				  required hardness.
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                | Quenching Oils : Those oils which are used in heat treating are called quenching oils. Such as mineral, fish,
				  vegetable and animal oils are often compounded and sold under trade names. These remove heat from the steel more
				  slowly and uniformly than water.
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                | Quick Change : It is the arrangement of gears on a lathe in such a manner as to permit change of feed by
				  shifting levers rather than removing and replacing gears.
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                | Quick Return : It is a device used in a reciprocating machine to make the return stroke much more rapid than
				  forward or cutting stroke. Such as shapers, planers and other metal-working machines.
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                | Quick Silver : It is an amalgam of tin that is used on the backs or mirrors. Quick silver is known as mercury.
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                | Quill : It is a hollow shaft or spindle.
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                | Quill Gear : A gear is called quill gear which is mounted on a hollow shaft.
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