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New B Model website

New B Model website

New B Model website

Product catalog summary
Overview: Jastram B Model Actuators are double-acting equal displacement cylinders used in marine steering systems. They are directly connected to a tiller, which moves the rudder when actuated. The sizing of these actuators depends on the maximum rudder torque required, which should be calculated and confirmed by a naval architect.
Specifications: The actuators are designed for a system pressure of around 500 PSI (35 BAR) for manual steering systems. They require specific installation components such as tiller bolts and hoses. Standard seal kits are available for maintenance, including JA-950002-1, B-38 seal kit; JA-950003-1, B-50 seal kit; and JA-950004-1, B-76 seal kit. Recommended oils are hydrocarbon-based ISO grade 32 oils.
Installation Recommendations: To ensure safe and efficient operation, the steering gear must be installed with the tiller properly clamped and keyed to the rudder stock. Rod end bolts should be US grade 5 or equivalent, and the rudder stock should turn without excessive friction. The actuator and tiller must swing freely, and all air should be bled from the hydraulic circuit before use.
Actuator Models and Specifications: The document lists various actuator models (e.g., B-38-120, B-50-190, B-76-300) with detailed specifications including torque ratings, cylinder bore, and stroke. The torque rating is determined at 1000 PSI (69 BAR) and a maximum rudder angle of 37°.
Warnings: Transmission oil or brake fluid should not be used with the Jastram system. The document emphasizes the importance of using the correct oil type to avoid system failure.
Additional Notes: The document includes a warning that data is subject to change without notice and highlights that Jastram B Model Actuators are ABS Type Approved for marine applications.
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Catalog excerpts

New B Model website-1

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 conrmed 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 Engineered For Life At Sea

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New B Model website-3

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...

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*Prices are pre-tax. They exclude delivery charges and customs duties and do not include additional charges for installation or activation options. Prices are indicative only and may vary by country, with changes to the cost of raw materials and exchange rates.