Types standard- variable pitch barrel constant rate variable rate hourglass conical (a)Helical compression springs.Push-wide load and deflection range-round or rectangular wire.Standard has constant coil diameter,pitch,and rate.Barrel,hourglass,and variable-pitch springs are used to minimize resonant surging and vibration. Conical springs can be made with minimum solid height and with constant or increasing rate (b)Helical extension springs.Pull-wide (c)Drawbar springs.Pull-uses comp- (d) Torsion springs.Twist- load and deflection range-round ression spring and drawbars to provide round or rectangular or rectangular wire,constant rate extension pull with fail-safe,positive stop. wire-constant rate.Types