Technical Information Steering Unit LAGZ /'/, WHITE together in motion

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Contents: Features ____________________________________________________________________________________ 5 Ordering details ______________________________________________________________________________ 5 Function, section _____________________________________________________________________________ 7 Versions ____________________________________________________________________________________ 9 Standard version- Open center with Non Reaction = OC / NR __________________________________________________9 Standard version- Open center with Reaction = OC / R _____________________________________________________...

Topics: • Features • Ordering details • Function, section • Functions in a steering circuit • Technical data • Pressure fluid technical data • Calculating the steering moment • Defining the steering cylinder and steering pump • Unit dimensions: Type LAGZ/ LAGZ LD • Ports: Type LAGZ/ LAGZ LD

• LAGZ steering units are used in hydraulic steering circuits of vehicles and mobile machines with large axle loads and travel speeds not exceeding 60 km/h. • With the aid of a steering unit even heavy vehicles can easily be steered. The absence of a mechanical connection between the steering unit and the steering axle allows the designer to realize solutions, which would be impossible with conventional steering systems. • In the event of a failure of the power assistance, vehicles can also be steered manually with the LAGZ. The required force is reduced by changing the transmission ratio. In...

Table 1 Model code details 1 Shown sizes are part of a preferred series, if you need others please ask your sales contact. 2 With reaction is available up to nom. size of260/60, all others are valid for Open Center and LD versions. 4 Only with the open center (OC) version 5 The response pressure of the shock valves must be 50 bar higher, however a maximum of 2.2 times that of the hydraulic pump pressure relief valves. (see §38 StVZO, German Road Traffic Licensing Regulation) Preferably 150 to 90; 200 to 140; 240 to 175 bar. 6 For thread dimensions see Unit dimensions: Type LAGZ/ LAGZ LD WHITE...

Function, section Control spool (1) of the control valve is rotated via the steering column in relation to control sleeve (2). This opens cross-sections between the spool and the sleeve. The pressurized oil acts on rotor sets (3 and 10) and sets them into motion. The oil is then fed via the rotor set to the steering cylinder. The rotation of both rotors acts on the sleeve, which then follows the rotary movement of the spool. The size of the opened cross-sections depends on the turning speed of the steering wheel and on the steering pressure; on Load-Sensing versions, it depends exclusively on...

5 Pressure relief valve 8 Suction check valve 9 Inlet check valve 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...

Versions Standard version- Open center with Non Reaction = OC / NR Mainly used in steering systems with fixed displacement hydraulic pumps. When no steering movement is performed, the connection between pump port (P) and tank port (T) is open (OC), and the pump flow is directed to the tank almost at zero pressure. Ports L1 (left) and R1 (right) are blocked in the neutral position (NR). In this way, external forces acting via the steering cylinder are supported without the driver perceiving any resulting reaction forces on the steering wheel (Non Reaction). Note: Steering units for vehicles with...

Standard version- Open center with Reaction = OC / R In the neutral position, the cylinder ports are connected with each other. External forces acting via the steering cylinder are perceived as reaction force by the driver on the steering wheel (Reaction). When the driver releases the steering wheel after the steering maneuver is completed, the wheels and the steering wheel automatically return to straight-ahead travel, provided that the steering geometry is suitable for this. Low-noise version Steering units of the LAGZ Open Center versions are generally delivered in the low-noise variant “N“....

Load signal, dynamic There is always a recommended oil flow of approx. 0.5 - 1.0 l/min in the LS-line from the priority valve to the steering unit that transmits the load (pressure) signal from the steering unit to the priority valve. Consequently, the steering unit gets warmed up by this and has approximately the same temperature as the oil. Thermal shocks are largely prevented. The LD version causes the priority valve to react faster. The hard point at the beginning of the steering movement is usually no longer perceivable - even under cold start conditions. Figure 4 LAGZ LD / R (left) and...

v#/. WHITEManual steering - Emergency mode During normal operation of the steering unit, when a sufficient amount of oil gets supplied to the steering unit, the torque required on the steering wheel is < 5 Nm. In the event that the oil supply fails, the steering unit operates in the emergency mode. The required steering pressure must then be generated by manual force on the steering wheel. With the LAGZ, the displacement can be reduced by switching one rotor set off. The pressure that can be generated manually depends on the size of rotor set 1 (see page 5) and the force applied to the steering...