Bosch Rexroth 4WE6 Direct-Operated Directional Spool Valve

Overview

The Bosch Rexroth 4WE6 is the size 6 member of the Rexroth WE family of direct-operated directional spool valves with solenoid actuation. It starts, stops and changes the direction of flow in a hydraulic circuit, and it is the valve most engineers picture when they think of a standard CETOP 3 solenoid valve on a power unit. According to Rexroth data sheet RE 23178, component series 6X is rated for a maximum operating pressure of 350 bar at ports P, A and B and a maximum flow of 80 l/min with DC solenoids or 60 l/min with AC solenoids. The valve is offered in 4/3-, 4/2- and 3/2-way versions with a wide range of spool symbols, so one body style covers cylinder control, motor reversing, unloading and pilot duties.

Seven Star LLC supplies the Bosch Rexroth 4WE6 to hydraulic workshops, OEM machine builders and plant maintenance teams across the Sultanate of Oman and the wider GCC. Typical requests come from hydraulic power units on oil and gas wellhead control panels, steel and aluminium plants in Sohar, port cranes in Salalah and Duqm, and mobile test rigs used by service contractors in Muscat. Our team in Muscat helps match a replacement valve to the type code on the existing nameplate, including spool symbol, voltage, electrical connection and manual override option, and provides engineering support.

Operating Principle

Inside the Bosch Rexroth 4WE6, a control spool slides in a precision bore within the cast housing. In the de-energised state the spool is held in its neutral or initial position by return springs, and the selected spool symbol decides which ports are open or blocked in that position. When a solenoid is energised, its armature pushes the spool through a plunger against the opposite spring until it reaches the switched position, opening the flow paths from P to A or P to B and connecting the other consumer port to tank. When the solenoid is de-energised, the spring returns the spool. Versions without spring return and versions with a detent are also available, where the spool stays in its last position until the opposite solenoid is energised.

Because the spool of the Bosch Rexroth 4WE6 is moved directly by the solenoid force, no pilot pressure is needed and the valve switches reliably even in circuits with low or variable pressure. The data sheet gives switching times according to ISO 6403 of 25 to 45 ms ON and 10 to 25 ms OFF for DC versions, and 10 to 20 ms ON and 15 to 40 ms OFF for AC versions, measured without flow at 40 °C and 46 cSt. The practical consequence is a simple, compact and very predictable component, but one whose flow capacity is limited by solenoid force; larger flows are handled by pilot-operated valves such as the WEH series.

Engineering Design of the Bosch Rexroth 4WE6

The Bosch Rexroth 4WE6 is built for subplate or manifold mounting with a porting pattern according to ISO 4401-03-02-0-05, with or without locating hole, and NFPA T3.5.1 R2-2002 D03. That interface is the common CETOP 3 footprint, so the Bosch Rexroth 4WE6 fits standard subplates, sandwich stacks and manifold blocks used throughout the region. Wet-pin high-power solenoids with detachable coils are used, and the coil can optionally be rotated by 90°. Electrical connection is available as individual connection on each solenoid or as a central connection, with options for interference protection circuits and connectors with indicator lights.

For the Bosch Rexroth 4WE6, Rexroth lists a weight of 1.45 kg for a valve with one solenoid and 1.95 kg with two solenoids, with any installation position permitted. The housing is primed as standard, while ordering options J3 and J5 provide improved and high corrosion protection tested to 240 h and 720 h salt spray according to EN ISO 9227, which is relevant for coastal and offshore sites. Manual override options range from a concealed override to mushroom-button and lockable versions, and optional spool position monitoring is available where a safety-related machine needs feedback of the switching state.

Key Features

The features below summarise why the Bosch Rexroth 4WE6 remains a standard choice for size 6 directional control.

• The Bosch Rexroth 4WE6 is available as a 4/3-, 4/2- or 3/2-way version with many spool symbols for different neutral position functions.
• The mounting interface follows ISO 4401-03-02-0-05 and NFPA D03, so it fits standard CETOP 3 subplates and manifolds.
• Ports P, A and B are rated for 350 bar in the standard version, with port T rated at 210 bar for DC and 160 bar for AC solenoids.
• High-power wet-pin solenoids with detachable coils allow coil replacement without opening the hydraulic circuit.
• The solenoid can optionally be rotated by 90° to suit the available space on a manifold.
• Optional manual overrides, including lockable and concealed designs, support commissioning and fault finding.
• Improved and high corrosion protection options are available for harsh coastal and outdoor environments.
• Optional spool position monitoring, UL-recognised coils and CSA approval are listed for machines that need them.

Industrial Applications

In Oman the Bosch Rexroth 4WE6 is found wherever a compact hydraulic power unit has to move cylinders or motors: wellhead and safety shutdown panels, hydraulic torque and tensioning equipment, valve actuator power packs, test benches, presses and material handling equipment in fabrication yards. In the aluminium smelter, steel and polymer plants of Sohar Industrial Port, the Bosch Rexroth 4WE6 drives clamps, gates and dampers. In marine and port service the valve appears on hatch covers, winch controls and crane auxiliaries, where the optional corrosion protection versions are a sensible choice.

Seven Star LLC supplies the Bosch Rexroth 4WE6 together with related Rexroth hydraulic components such as the Bosch Rexroth MHDBD10K2-1X/315V pressure relief valve, the Bosch Rexroth A10VSO axial piston variable pump and the Bosch Rexroth R928006678 hydraulic filter element, which keeps the oil clean enough for spool valves. The data sheet specifies a maximum contamination level of class 20/18/15 according to ISO 4406 (c), so filtration is part of every reliable installation. Customers in Muscat, Sohar, Duqm and Salalah use us as a single point of supply for valves, pumps and filtration on the same power unit.

Technical Specifications

The table lists Bosch Rexroth 4WE6 data from data sheet RE 23178 (edition 2019-01) for component series 6X; the exact values for a given order depend on the full type code.

How to Order

To order the Bosch Rexroth 4WE6, send Seven Star LLC the full type code or material number from the valve nameplate, or describe the spool symbol, voltage and connector you need. Our instrumentation and hydraulics division in Muscat will confirm the correct variant, share the technical datasheet for download and prepare a formal quotation. Seven Star LLC supplies Rexroth hydraulic components to customers across Oman and the GCC with engineering support in Muscat.