Question

a) What are the disadvantages of using single coil springs for mechanical seals? b) What are the main advantages associated with the use of multi-coil springs?

Answer 1

(a) - The disadvantages of using single coil springs for mechanical seals are that the very non uniform spring force is applied due to single coil which can produce waviness and can cause distortion to the seal faces in large sizes. And also the spring can be distorted at higher surface speed.

(b) - A multi coil spring consists of series of small coil springs that are circumferentially spaced around the seal face. Due to the spacing, uniform load is applied on the seal face which reduces the waviness and distortion concerning spring forces. And also the arrangement is less responsive to distortion due to higher speed up to 4500 rpm.