Problem 17.23
An overflow valve, shown in sketch b, has a piston diameter of 15 mm and a slit length of 5 mm.
The spring has mean coil diameter D = 10 mm and wire diameter d = 2 mm. The valve should
open at 1 bar pressure and be totally open at 3 bar pressure when the spring is fully compressed.
Calculate the number of active coils, the free length, and the pitch of the spring. The shear
modulus for the spring material G = 80 GPa. The spring ends are squared and ground.
Determine the maximum shear stress for this geometry.
15
5
