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Types of mechanical forces

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A force exerted on a body can cause a change in either the shape or the motion of the body.The unit of force in SI system is the Newton(N) and CGS system is dyne.No solid body is perfectly rigid and when force are applied to it,changes in dimension occur.such changes are not always perceptible to the human eye since they are negligible. For the example,The span of a bridge will sag under the weight of a vehicle and a spanner will bend slightly when tightening a nut. It is also important for civil engineers and designers to appreciate the effects of forces on materials.Together with their mechanical properties of the materials. There three main types of mechanical forces that can act on a body.They are 1)Tensile force 2) compressive force and 3) shear force
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PROPERTIES OF CUTTING FLUIDS:

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To get the optimum benefits, the cutting fluid should possess the following qualities.

1) They should possess good lubricating properties to minimise the friction.

2)They should possess high heat absorption capacity so as to carry away the heat generated.

3)They should present no fire or accidental hazards.

4) They should not cause skin irritation.

5)They should not emit obnoxious odours and vapours harmful to the operator, workpiece or surrounding area.

6) They should be of low viscosity to permit free flow and easy separation from chips collected.

7)They should prevent rusting of the
Machine slidings and working surfaces.

8) They should be suitable for a variety of cutting operations, and should be easily available at low price so as to minimise production cost.

9) They should be chemically stable.

10) they should not deteriorate in storage.

11) They should have high flash point.

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