Page 253 - Softbound_Edition_19_en
P. 253

BH4x4
                                                                                                       Spool valve


            Spool valve
                                                                 NG4-Mini
            Flange construction
             ◆  hand operated
             ◆  4/3-way with spring centred mid position
             ◆  4/2-way with spring reset
             ◆  4/2- and 4/3-way detented
             ◆  Q  = 20 l/min
                max
             ◆  p  = 350 bar
                max


            DESCRIPTION                                          APPLICATION
            Direct operated spool valve, hand operated with 4 connections in 5   Spool valves are mainly used for controlling direction of movement
            chamber design. Spool detented or with spring. Without actuation,   and stopping of hydraulic cylinders and motors. The direction of
            the  spool  is  held  in  the  center  position  by  the  spring  (4/3),  or    movement is determined by the position of the spool and its symbol.
            switched  back  to  the  offset  position  (4/2).  With  the  detent,  the   Manually or mechanically operated valves are particularly suitable
            spool is held in the last switching position selected. Precise spool   for use in installations where no electric current is available or for
            fit, low leakage, long service life time. Spool made from hardened   applications in explosion hazard areas. Miniature values are used

            steel, body from high quality hydraulic cast steel.         where both, reduced dimensions and weight are important.


            TYPE CODE

                                                                                            B  H  4     /     -     #
             Mounting interface acc. to Wandfluh standard
             Hand lever

             Number of control ports
             Designation of symbols acc. to table   Operation a-side    …a
                                            Operation b-side      …b
             Hand lever with spring reset or spring centred        f
             Hand lever dentented                                  r

             Sealing material               NBR
                                            FKM (Viton)           D1

             Design index (subject to change)
             1.5-20

            GENERAL SPECIFICATIONS                               HYDRAULIC SPECIFICATIONS
             Designation        4/2-, 4/3-spool valve             Working pressure   p  = 350 bar
                                                                                     max
             Construction       Direct operated                   Tank pressure      p   = 100 bar
                                                                                     T max
             Mounting           Flange construction               Maximum volume flow  Q  = 20 l/min, see characteristics
                                                                                      max
             Nominal size       NG4-Mini according to Wandfluh
                                standard                          Leakage volume flow  See characteristics
             Actuation          Hand operated                     Fluid              Mineral oil, other fluid on request
             Ambient temperature  -25…+70 °C (NBR)                Viscosity range    12 mm /s…320 mm /s
                                                                                         2
                                                                                                  2
                                -20…+70 °C (FKM)                  Temperature range   -25…+70 °C
             Weight             0,87 kg                           fluid
             MTTFd              150 years                         Contamination      Class 20 / 18 / 14
                                                                  efficiency
                                                                  Filtration         Required filtration grade ß 10…16 ≥ 75,
                                                                                     see data sheet 1.0-50





                                www.wandfluh.com  Illustrations are not binding  Data subject to change  1/4  Edition: 16 33  1.5-20 E
                                                                                                            Page 253
   248   249   250   251   252   253   254   255   256   257   258