M e c h a n i c a l T o o l s

Both in maintenance and in repair of machines all kinds of fitting operations are applied. An important role is played by disassembling and assembling operations. Special instruments are used for performing these operations.

Among the variety mechanical tools used for disassembling and assembling machine parts and in their repairing are wrenches. According to their construction and wrenches may be of different types: single-ended and double-ended nut wrenches, adjustable wrenches, socket wrenches and special.

A nut wrench is used for screwing and unscrewing nuts. It consists of a handle and a head with an opening known as the span.

Adjustable wrenches may be used for unscrewing nuts and bolts of different dimensions.

Socket wrenches are applied in cases when nuts or bolt heads located in recesses are сhardly accessible for a nut wrench.

Special wrenches are used for unscrewing and screwing nets of a definite type.

Wrenches are used by drivers for repairing cars, in locksmith’s shops and fitter’s shops. Fitters use them to screw different types of machine parts as: washers, bolts, shafts, etc. plumbers use them to repair pipes, taps, etc. Besides different types of wrenches there are round pliers or needle nose pliers which are widely used by locksmiths, electricians and other specialists for gripping, screwing or cutting off thin metal and wires.

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