accept no responsibility for possible errors in catalogues, brochures, and other printed material. WHITE reserves the right to alter its products without notice. This also applies to products already on order provided that such alterations can be made subsequent changes being necessary in specifications already agreed. All trademarks in this material are the property of the respective companies. WHITE and the WHITE logotype are trademarks of WHITE Drive Motors & Steering LLC and WHITE Drive Motors and Steering Sp. z o.o.. All rights reserved.

accept no responsibility for possible errors in catalogues, brochures, and other printed material. WHITE reserves the right to alter its products without notice. This also applies to products already on order provided that such alterations can be made subsequent changes being necessary in specifications already agreed. All trademarks in this material are the property of the respective companies. WHITE and the WHITE logotype are trademarks of WHITE Drive Motors & Steering LLC and WHITE Drive Motors and Steering Sp. z o.o.. All rights reserved.

WHITE can accept no responsibility for possible errors in catalogues, brochures, and other printed material. WHITE reserves the right to alter its products without notice. This also applies to products already on order provided that such alterations can be made without subsequent changes being necessary in specifications already agreed. All trademarks in this material are the property of the respective companies. WHITE and the WHITE logotype are trademarks of WHITE Drive Motors & Steering LLC and WHITE Drive Motors and Steering Sp. z o.o.. All rights reserved.

WHITE can accept no responsibility for possible errors in catalogues, brochures, and other printed material. WHITE reserves the right to alter its products without notice. This also applies to products already on order provided that such alterations can be made without subsequent changes being necessary in specifications already agreed. All trademarks in this material are the property of the respective companies. WHITE and the WHITE logotype are trademarks of WHITE Drive Motors & Steering LLC and WHITE Drive Motors and Steering Sp. z o.o.. All rights rese

Chapter 1 General Information Topics: • • • Description and Advantages Hydraulic Circuit Explanation Valve Description WHITE can accept no responsibility for possible errors in catalogues, brochures, and other printed material. WHITE reserves the right to alter its products without notice. This also applies to products already on order provided that such alterations can be made without subsequent changes being necessary in specifications already agreed. All trademarks in this material are the property of the respective companies. WHITE and the WHITE logotype are trademarks of WHITE Drive Motors...

The Steering control unit (SCU) is fully fluid linked. This means there is no mechanical connection between the steering unit, the pump and the steering cylinders. The unit consists of a manually operated directional control servo valve and feedback meter element in a single body. It is used principally for fluid linked power steering systems, but it can be used for some servo-type applications or any application where visual positioning is required. The close coupled, rotary action valve performs all necessary fluid directing functions with a small number of moving parts. The manually actuated...

7 The following special considerations should be addressed when applying power beyond steering: • Auxiliary valves (connected to PB) must be open center type. Slight bump or kick may be felt in steering wheel when auxiliary functions are activated during steering operations. Pump flow not used for steering is available at power beyond (PB) outlet, except at steering stops where total pump flow goes over the system relief valve. Avoid auxiliary functions that require constant flow while steering. Flow is only directed to the tank port when steering is operated. Avoid systems where return flow...

Construction Industry Neutral Circuits: Load Sensing Load Sensing Circuits Load sensing power steering uses conventional or load sensing power supplies to achieve load sensing steering. The use of a load sensing steering unit and a priority valve in a normal power steering circuit offers the following advantages: • Provides smooth pressure compensated steering be- cause load variations in the steering circuit do not affect axle response or maximum steering rate. Provides true power beyond system capability by splitting the system into two independent circuits. Pressure transients are isolated...

9 Load Sensing Circuits – Signal Systems Two types of load sensing signal systems are available—Dynamic and Static. Dynamic Signal—Used for more difficult applications. The dynamic signal systems offer the following benefits: • Faster steering response. • Improved cold weather start-up performance. • Increased flexibility to solve problems related to system performance and stability. Dynamic Signal—Open Center Pump Dynamic Signal—Load Sensing Pump Figure 6 Dynamic Signal—Open Center Pump Figure 7 Dynamic Signal—Load Sensing Pump Static Signal—Open Center Pump Static Signal—Used for conventional...

Control Unit Circuit with Open Center Priority Valve (Static Signal) Fixed Displacement Pump Load Sensing Steering System with Fixed Displacement Pump (Open Center Circuit) Figure 8 Static Signal Work Circuits: Non-Load Reaction and Load ReactionNon-Load Reaction A non-load reaction steering unit blocks the cylinder ports in neutral, holding the axle position whenever the operator releases the steering wheel. Mechanism Direct Mechanical Link Steering Control Pressure and F owCompensated Pump Closed Center System Non-Load Reaction Circuit Figure 9 Closed Center System (Non-Load Reaction Circuit)...

11 The cylinder system used with load reaction units must have equal oil volume displaced in both directions. The cylinders should be a parallel pair (as shown) or one double rod end unit. Do not use with a single unequal area cylinder system. Figure 10 Open Center System Load Reaction Circuit Valve Description Integral valves are available for the steering control unit. Included are: Inlet Relief Valve, Cylinder Port Shock Valves, LS-Relief Valve, and Anti-Cavitation Valves for cylinder ports. In addition, a Manual Steering Check Valve for limited manual steering is included. The integral valves...