Profile: Central Springs & Pressings Limited manufactures springs and flat metal components for a variety of sectors including aerospace, the Ministry of Defense, pharmaceutical & the car industry. Extension springs are usually made from round wire. They can be made from regular carbon steels, chrome vanadium, silico-manganese and other alloy steels. Standard split rings contain materials such as carbon steel wire and stainless steel wire. Wave spring washers are used to control end float and bearing pre-load. Curved washers provide end float control.