Распределители золотниковые, пилотного управления, с электрогидравлическим управлением H-4WEH…XD

Description Size 10 … 32 Component series 4X, 7X, 6X Maximum operating pressure 350 bar Maximum flow 1100 l/min Area of application in accordance with the Explosion Protection Directive 2014/34/EU: I M2; II 2G Type of protection valve: – Ex h I Mb X according to EN 80079-38 – Ex h IIC T4 Gb X according to EN 80079-36 Type of protection, solenoid coil: – Ex db I Mb nach EN 60079-1 – Ex db IIC T4 Gb nach EN 60079-1 Solenoid coil certified according to IECEx Features 4/3- or 4/2-way version For intended use in potentially explosive atmosphere Internal or external pilot control Subplate mounting Porting pattern according to ISO 4401 Spring centering, spring end position or hydraulic end position Wet-pin DC solenoids Manual override Electrical connection as individual connection with cable gland Switching time adjustment, optional Preload valve in channel P of the main valve, optional Product description Type H-4WEH 16…XD... The valve type H-4WEH is a directional spool valve with electro-hydraulic actuation. It controls the start, stop and direction of flow. The directional valve basically consists of the main valve with housing (1), the main control spool (2), one or two return springs (3.1) and (3.2), as well as the pilot control valve (4) with one or two solenoids "a" (5.1) and/or "b" (5.2). For unobjectionable functioning, the hydraulic system has to be bled properly. The main control spool (2) in the main valve is held in the zero or initial position by the springs or by means of pressurization. In the initial position, the two spring chambers (6) and (8) are connected with the tank in a depressurized form via the pilot control valve (4). The pilot control valve is supplied with pilot oil via the control line (7). Supply can be effected internally or externally (externally via port X). Upon actuation of the pilot control valve, e.g. solenoid "a", the pilot control spool (10) is moved to the left and thus, the spring chamber (8) is pressurized with pilot pressure. The spring chamber (6) remains depressurized. The pilot pressure acts on the left side of the main control spool (2) and moves it against the spring (3.1). This connects ports P with B and A with T in the main valve. When the solenoid is switched off, the pilot control spool returns into the initial position (except for impulse spool). The spring chamber (8) is unloaded to the tank. The pilot oil from the spring chamber is displaced into channel Y via the pilot control valve. The pilot oil supply and return can be effected internally or externally. The manual override (9) allows the control spool (10) to be moved without solenoid energization. Notice: The main control spool (2) is held in a central position by the return springs (3.1) and (3.2) in spring chambers (6) and (8) without pilot pressure, even if the valve is positioned for example vertically. Due to the design principle, internal leakage is inherent to the valves, which may increase over the life cycle. Pilot oil supply "H-WEH