Proportional directional valves, pilot operated, without electrical position feedback 4WRZ ...XE

Description

• Size 10, 16, 25, 32
• Component series 7X
• Maximum operating pressure 350 bar
• Maximum flow 1600 l/min
• Area of application in accordance with the Explosion Protection Directive 2014/34/EU: II 2G; II 2D
• Type of protection valve:
  – Ex h IIC T4 Gb X according to EN 80079-36
  – Ex h IIIC T115°C Db X according to EN 80079-36
• Type of protection, solenoid coil:
  – Ex eb mb IIC T4 Gb according to EN 60079-7 / EN 60079-18
  – Ex tb IIIC T115°C Db according to EN 60079-31
• Solenoid coil certified according to IECEx

Features

• 4/2 or 4/3 directional design
• For intended use in potentially explosive atmosphere
• For the control of flow direction and size
• For subplate mounting
• Porting pattern according to ISO 4401
• Spring-centered control spool
• Actuation by means of the pilot control valve (3-way pressure reducing valve)
• Solenoid coil is rotatable by 90°
• Electrical connection as individual connection with cable gland

Product description

Valves of the type 4WRZ... are pilot-operated proportional directional valves that are actuated by means of proportional solenoids. Their function is to control the flow direction and size.

The proportional solenoids are controlled by external control electronics.

Set-up

The valve basically consists of:

• Pilot control valve (4) with proportional solenoids (2 and 3)

• Pressure reducing valve (9)

• Main valve (5) with main control spool (6) and centering spring (7)

Function

• With de-energized solenoids (2 and 3), the main control spool (6) is held in central position by means of a centering spring (7)

• The main control spool (6) is controlled by the pilot control valve (4); the main control spool is proportionally moved, e.g. by actuating solenoid "b" (3)
  • The control spool (1) is moved to the right, pilot oil enters the pressure chamber (8) via the pilot control valve (4) and deflects the main control spool (6) proportionally to the electric input signal to the left
  • Connection from P → A and B → T via orifice-type cross-sections with progressive flow characteristic

• Pilot oil supply to the pilot control valve internally via port P or externally via port X

• Switching off the solenoid (3)
  • The control spool (1) and main control spool (6) are moved back into the central position

• Flow depending on spool position from P → A and B → T or P → B and A → T.

Notice:

With pilot control valves of the version "3DREP 6 C", only one solenoid may be actuated at a time.

Type 4WRZ...-7X./...

Type code

Technical data

general

hydraulic

electrical

Information on explosion protection

Special application conditions for a safe application

• Connection lines must be passed in a strain-relieved way. The first mounting point must be within 150 mm of the cable and line entry.

• In case of valves with two solenoids, maximally one of the solenoids may be energized at a time.

• Only direct voltage or a pulse-width modulated signal with a pulse voltage ≤28 V and frequency ≥160 Hz … up to max. 500 Hz may be used.

• The maximum temperature of the surface of the valve jacket is 115 °C. This has to be considered when selecting the connection cable and/or contact of the connection cable with the surface of the jacket is to be prevented.

Control electronics

(For applications outside these values, please consult us!)

Diagrams/characteristic curves

(measured with symbol E, W6-, EA, W6A, HLP46, ϑOil = 40 ±5 °C)

Size 10

Rated flow 25 l/min

(P → A; B → T or P → B; A → T)

Rated flow 50 l/min

(P → A; B → T or P → B; A → T)

Rated flow 85 l/min

(P → A; B → T or P → B; A → T)

Transition function with stepped electric input signals

(measured with pilot pressure pSt = 50 bar)

Size 16

Rated flow 125 l/min

(P → A; B → T or P → B; A → T)

Rated flow 180 l/min

(P → A; B → T or P → B; A → T)

Transition function with stepped electric input signals

(measured with pilot pressure pSt = 50 bar)

Size 25

Rated flow 220 l/min

(P → A; B → T or P → B; A → T)

Rated flow 325 l/min

(P → A; B → T or P → B; A → T)

Transition function with stepped electric input signals

(measured with pilot pressure pSt = 50 bar)

Size 32

Rated flow 360 l/min

(P → A; B → T or P → B; A → T)

Rated flow 520 l/min

(P → A; B → T or P → B; A → T)

Transition function with stepped electric input signals

(measured with pilot pressure pSt = 50 bar)

(measured with HLP46, ϑÖl = 40 ±5 °C)

Symbols/Circuit diagrams

Notices:

• With symbols W, W6-, W8-, W9-, W6A and W6B, there is - in the “0” spool position - a connection from A → T and from B → T with less than 2% of the relevant nominal cross-section.

• Representation according to ISO 1219-1.

• Hydraulic interim positions are shown by dashes.

Pilot oil supply

3 spool positions	2 spool positions (Version ".A)"
		"4WRZ" External pilot oil supply, external pilot oil return The pilot oil is supplied from a separate control circuit (external). The pilot oil return is not directed into channel T of the main valve, but is separately directed to the tank via port Y (external).
		"4WRZ…E" Internal pilot oil supply, external pilot oil return The pilot oil supply is implemented from channel P of the main valve (internally). The pilot oil return is not directed into channel T of the main valve, but is separately directed to the tank via port Y (external). In the subplate, port X is to be closed.
		"4WRZ…ET" Pilot oil supply internal, pilot oil return internal The pilot oil supply is implemented from channel P of the main valve (internally). The pilot oil is directly returned to channel T of the main valve (internally). In the subplate, ports X and Y are to be closed.
		"4WRZ…T" External pilot oil supply, internal pilot oil return The pilot oil is supplied from a separate control circuit (external). The pilot oil is directly returned to channel T of the main valve (internally). In the subplate, port Y is to be closed.

Electrical connection

The type-examination tested solenoid coil of the valve is equipped with a terminal box, a type-examination tested cable entry and a type-examination tested blind plug.
The connection is polarity-independent.

Notice:

When establishing the electrical connection, the protective grounding conductor (PE) must be connected correctly.

Suppressor diode 47 V, 1.5 kW

Properties of the connection terminals and mounting elements

Connection line

Notice:

Only use finely stranded conductors if they have pressed-on wire end ferrules.

Over-current fuse and switch-off voltage peaks

Notices:

Corresponding to the rated current, a fuse according to DIN 41571 and EN/IEC 60127 has to be connected upstream of every valve solenoid (max. 3 x Irated).

The shut-off threshold of the fuse has to match the prospective short-circuit current of the supply source.

The short-circuit current of the supply source to be expected may amount to a maximum of 1500 A.

This fuse may only be installed outside the potentially explosive atmosphere or must be of an explosion-proof design.

When inductivities are switched off, voltage peaks result which may cause faults in the connected control electronics. For this reason, the solenoid coil comprise an interference protection circuit which dampens this voltage peak to the voltage value shown in the table.

Dimensions

Size 10

Dimensions in mm

Required surface quality of the valve contact surface

Notice:

The dimensions are nominal dimensions which are subject to tolerances.

Valve mounting screws (separate order)

Size 16

Dimensions in mm

Required surface quality of the valve contact surface

Notice:

The dimensions are nominal dimensions which are subject to tolerances.

Valve mounting screws (separate order)

Size 25

Dimensions in mm

Required surface quality of the valve contact surface

Notice:

The dimensions are nominal dimensions which are subject to tolerances.

Valve mounting screws (separate order)

Size 32

Dimensions in mm

Required surface quality of the valve contact surface

Notice:

The dimensions are nominal dimensions which are subject to tolerances.

Valve mounting screws (separate order)

Subplates (separate order) with porting pattern according to ISO 4401, see data sheet 45100.

Notice:

Subplates are no components in the sense of directive 2014/34/EU and can be used after the manufacturer of the overall system has conducted an assessment of the risk of ignition. The "G...J3" versions are free from aluminum and/or magnesium and galvanized.

Downloads

	Proportional directional valves, pilot-operated, without electrical position feedback Data Sheet | RE29115-XE | 2021-04-01 | English | PDF | 960k Product Groups: Proportional directional valves Type 4WRZ …XE
	Proportional directional valves, pilot-operated, without electrical position feedback Manual | RE29115-XE-B | 2021-02-01 | English | PDF | 2.1MB Product Groups: Proportional, high-response and servo valves Type 4WRZ..7X/...XE...
	Explosion-protected hydraulic products for industrial and mobile applications Brochure | R999000373 | 2017-03-01 | English | PDF | 5.8MB Product Groups: Pumps, CD - single rod cylinder, Proportional, high-response and servo valves, Axial piston pumps, Mobile controls Product overview