Question

A close-coiled helical spring has a mean coil diameter 120 mm. A load of 4 kN causes a deflection of 50 mm and a maximum stress of 500 MPa. Calculate 4.1. a) The wire diameter b) The number of coils c) The energy absorbed when subjected to the maximum load d) The spring stiffness 4.2. By use of a clearly labelled neat sketch, show that the deflection in a close-coiled 12] where Wis ; where W is the axial load on the spring, D is the 8WD3n spring can be given by o -Gd4 mean coil diameter, n is the number of coils, G is the Modulus of Rigidity for the spring and d is the wire diameter. [10]

Answer 1

Gd4 4- 4-

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