The ramrod pushes the piston directly with minimal parts and simple structure incorporating rugged and high reliability design. Hydraulic power is transmitted from a heavy rod through the scotch yoke design resulting a smooth transition movement.
Such a design give higher force input the developed torque at open and close position is more than twice of mid position (45 degrees). This is similar to the required torque to open and close operation of a ball valve. (Refer to ball valve torque requirement chart)
Local position indicator is easily viewed. (Built in limit switch)