Photo Courtesy of Oceanline Shipyard Jastram Model B Steering Gear Jastram B Model Actuators are double-acting equal displacement cylinders, which are directly connected to a tiller. When the B Model is actuated it moves the tiller, which in turn moves the rudder. The actuator sizing is primarily dependent on the maximum rudder torque required. Once the required rudder torque is known the appropriate actuator size can be selected. Calculating the rudder torque is complex. An incorrect calculation can result in failure of the steering system. Torque calculations should be confirmed by a naval architect or designer. For more information on actuator sizing please contact your local Jastram distributor. Type Approved Product; see details on back page

Basic Manual Hydraulic Steering System Actuator & Helm Pump Sizes Helm Pumps Torque ~ 2 x 35˚ @1000 PSI Displacement Wheel In³ cm³ Model Turns Lbs-Ft N-M STEERING SYSTEM SPECIFICATIONS (INCH) Items to note on small steering systems: • Double Acting Relief and Bypass (DARBs) valves are suggested to protect the steering gear • Header tanks or autofill valves are suggested to prevent the introduction of air or the loss of steering due to low oil levels • A system pressure of around 500 PSI (35 BAR) is suggested for manual steering systems • Shut off valves are suggested at each component in the hydraulic...

General Steering Gear Arrangments Twin Rudder Twin Actuator Single Actuator Single Rudder Items to note on installation: To ensure SAFE and EFFICIENT operation the steering gear must be installed under the following conditions: • Tiller is properly clamped and keyed to the rudder stock. Clearance between key and keyway is not excessive • Rod end bolts (shipyard supply) clamping the actuator rod end to the tiller are US grade 5 or equivalent and secured with a lock nut • Suitable bearing support is provided for the rudder stock • Rudder stock can turn without excessive friction • Tiller and actuator...