Inverse Prop. Pressure-Relief Cart., Size Q max = l/min (6 gpm), p max = bar (58 psi) Direct acting, electrically operated Description inverse proportional pressure-relief valves are direct acting screw-in cartridges of sliding-spool design with a falling pressure/current characteristic and a 3/-6 UNF mounting thread. With these pressure-relief cartridges, the relief pressure is dependent on the electrical control signal and can be continuously varied. When the solenoid is de-energised (initial position), the relief pressure is the nominal pressure of the applicable spring range (failsafe function). Any pressure at port is additive to the valve setting at port, therefore port should preferably be connected directly to tank. In control mode, the relief pressure is inversely proportional to the change in the required value (amplifier output current). In order to obtain precise pressure settings over the whole of the required pressure range Compact construction for cavity type AL 3/-6 UNF Operated by a proportional solenoid Nominal pressure when solenoid de-energised (fail-safe function) 6 pressure ranges available All exposed parts with zinc-nickel plating High pressure wet-armature solenoids The slip-on coil can be rotated, and it can be replaced without opening the hydraulic envelope With integral manual pressure setting Can be fitted in a line-mounting body (optimum resolution), the pressure relief cartridges are available in six spring ranges. If a proportional solenoid is faulty, for example, the integral manual pressure setting enables the required pressure to be set mechanically. Inverse proportional pressure-relief cartridges are predominantly used in mobile and industrial applications to allow a pressure in hydraulic installations to be limited electro-proportionally. All external parts of the cartridge are zinc-nickel plated to DIN 5 979 and are thus suitable for use in the harshest operating environments. The slip-on coils can be replaced without opening the hydraulic envelope and can be positioned at any angle through 36. If you intend to manufacture your own cavities or are designing a line-mounting installation, please refer to the section Related data sheets. Symbol 3 Technical data General characteristics Designation inverse proportional pressure-relief cartridge Design direct acting, electrically operated Mounting method screw-in cartridge 3/-6 UNF Tightening torque Nm ± % (3 ft-lbs ± %) Size nominal size..., cavity type AL Weight.58 kg (.8 lb) Reference: -P-585-EN- Issue:.8 /6
General characteristics Mounting attitude unrestricted (preferably vertical, coil down) Ambient temperature range -5 C +6 C (77 F + F) Hydraulic characteristics Maximum operating pressure (p max ) - main port - port bar (58 psi) 5 bar ) (36 psi) Maximum flow rate l/min ) (6 gpm) Nominal pressure ranges (p N ) 5 bar, 63 bar, bar, (35 psi, 86 psi, psi) 6 bar, 3 bar, 35 bar (3 psi, 33 psi, 5 psi) Leakage flow rate Flow direction pressure range 5 / 63 bar (35 / 86 psi) bar ( psi) 6 bar (3 psi) 3 bar (33 psi) 35 bar (5 psi). l/min. l/min.5 l/min.3 l/min. l/min see symbols (.3 gpm) (.5 gpm) (.6 gpm) (.8 gpm) (. gpm) Hydraulic fluid HL and HLP mineral oil to DIN 5 5; for other fluids, please contact BUCHER Hydraulic fluid temperature range -5 C +7 C (-77 F +58 F) Viscosity range Minimum fluid cleanliness Cleanliness class to ISO 6 : 999 5 38 mm /s (cst), recommended...3 mm /s (cst) class 8/6/3 ) To prevent any pressure surges, port must be routed to tank with the least possible back-pressure. Any tank pressure acting at port is additive to the pressure setting at the main port. ) Depending on the nominal pressure stage. Electrical characteristics Supply voltage Control current Power consumption at max. control current Coil resistance R - cold value at C - max. warm value Recommended PWM frequency (dither) Hysteresis with PWM Reversal error with PWM Sensitivity with PWM Reproducibility with PWM V DC, V DC V = 6 ma, V = 8 ma max. 7.5 W V =.35 / V = 7. V = 6.8 / V = 6.9 Hz % I N % I N < % I N < % p N Switching time 6 9 ms (Solenoid ON) 6 ms (Solenoid OFF) These times are strongly influenced by fluid pressure, flow rate and viscosity, as well as by the dwell time under pressure. Relative duty cycle Protection class to ISO 653 / EN 6 59 Electrical connection % IP 65 / IP 67 / IP 69K, see Ordering code (with appropriate mating connector and proper fitting and sealing) DIN EN 753-83, 3-pin P+E (standard) for other connectors, see Ordering code /6 -P-585-EN-/.8
Performance graphs measured with oil viscosity 33 mm /s (cst) p = f (I) Pressure adjustment characteristic (Q = l/min) 7 P3.ai p = f (I) Pressure adjustment characteristic (Q = l/min) 35 P35.ai 6 5 p N 63 bar 3 5 p N 3 bar p N 35 bar 3 p N 5 bar 3 6 8 5 6 7 8 6 I [ma] p = f (Q) Pressure - Flow rate characteristic p N = 5 bar 3 P36.ai 8 6 Q [l/min] p = f (Q) Pressure - Flow rate characteristic p N = bar 8 6 P38.ai 6 8 5 Q [l/min] p = f (Q) Pressure - Flow rate characteristic p N = 3 bar 3 P.ai 5 5 p N 6 bar p N bar 3 6 8 5 6 7 8 6 I [ma] p = f (Q) Pressure - Flow rate characteristic p N = 63 bar 9 8 7 6 5 3 P37.ai 8 6 8 Q [l/min] p = f (Q) Pressure - Flow rate characteristic p N = 6 bar 8 5 9 6 3 P39.ai 6 8 3 Q [l/min] p = f (Q) Pressure - Flow rate characteristic p N = 35 bar P.ai 5 5 5 3 3 5 6 7 8 9 Q [l/min] 3 5 6 Q [l/min] -P-585-EN-/.8 3/6
5 Dimensions & sectional view 3/ 6UNF 8 (.) M A = [Nm] ± % (3 ft lbs± %) 3 35. (5.33) 7. (.3) 8 (.89) 79.6 (3.3) 3 35.5 (.) (.6) (.87) 39 (.5) 6 (.) M A =.7 [Nm] ± % ( ft lbs ± %) 3 M A = [Nm] ± % (7 ft lbs ± %) B A M A = [Nm] ± % (.7 ft lbs ± %) Seal kit NBR no. DS-8-N ) Item Qty. Description O-ring no. 7 7.7 x.78 N9 O-ring no.. x.78 N9 3 O-ring 6. x. FKM Backup ring.7 x.5 x. FI75 IMPORTANT! ) Seal kit with FKM (Viton) seals no. DS-8-V Integral air-bleeding If necessary, air can be purged from these proportional pressure-relief cartridges by using the integral air-bleed screw (Item B). The procedure is as follows: F Protective cap G Air-bleed screw Steps: 7. Remove the protective cap. 8. Slacken the air-bleed screw approx. turns. 9. Switch the pressure-relief cartridge on/off several times until no more air bubbles escape.. Tighten the air-bleed screw (M A = Nm %).. Fit the protective cap. /6 -P-585-EN-/.8
6 Installation information IMPORTANT! To achieve the proportional pressure-relief cartridge's maximum performance rating, fit the solenoid coil as shown (plug socket upwards or to screw-in thread). When fitting the cartridges, note the mounting attitude (preferably vertical, with coil down " automatic air bleed) and use the specified tightening torque. No adjustments are necessary, since the cartridges are set in the factory. Only qualified personnel with mechanical skills may carry out any maintenance work. Generally, the only work that should ever be undertaken is to check, and possibly replace, the seals. When changing seals, oil or grease the new seals thoroughly before fitting them. To prevent any pressure surges, port must be routed to tank with the least possible back-pressure. Any tank pressure acting at port is additive to the pressure setting at the main port. 7 Manual pressure setting The inverse proportional pressure relief cartridges are equipped with emergency pressure adjustment as standard. If the electrical control fails, the preset maximum pressure value is set. This can be lowered mechanically to a desired pressure value. This emergency pressure setting is not intended for pressure value adjustments in solenoid operation. IMPORTANT! Any changes to the emergency pressure setting have a direct effect on the factory settings. E D 3 MA = [Nm] ± % (7 ft lbs ± %) C Setting the pressure manually Steps:. Remove the protective cap.. Slacken the lock nut (3 A/F). 3. Unscrew (turn to left) the adjusting spindle ( A/F) until the required pressure is set.. Tighten the lock nut (3 A/F). 5. Fit the protective cap. To reset the inverse proportional pressure-relief cartridges to their initial position (the factory setting), a constant flow rate and a pressure gauge that measures the pressure in the main port are needed. The pressure setting must not exceed the nominal pressure of the spring range in use. The procedure is as follows: H I J Protective cap Lock nut (3 A/F) Adjusting spindle for pressure setting Restoring the factory settings Steps:. Solenoid de-energised.. Remove the protective cap. 3. Slacken the lock nut (3 A/F).. Unscrew the adjusting spindle ( A/F) to its end-stop, then screw it in until the pressure on the gauge reaches the nominal pressure (p N ) of the spring range in use. 5. Tighten the lock nut (3 A/F). 6. Fit the protective cap. -P-585-EN-/.8 5/6
8 Ordering code D B D T C - L G - 35 - _ - D D = pressure control valve B = pressure relief function D = direct acting T = proportional solenoid C... Q = standard model - see relevant data sheets Z... R = special features - please consult BUCHER = pressure function L = cavity type AL G = proportional solenoid, inverse type (pulling) 35 = pressure range 35 bar 3 = pressure range 3 bar 6 = pressure range 6 bar = pressure range bar 63 = pressure range 63 bar 5 = pressure range 5 bar = nominal size for pressure ranges 35 and 3 3 = nominal size 3 for pressure ranges 6 and = nominal size for pressure ranges 63 and 5 (blank) = NBR (Nitrile) seals (standard) V = FKM (Viton) seals (special seals - please contact BUCHER)... 9 = design stage (omit when ordering new units)... = voltage e.g. ( V) D = current DC G = ISO / DIN 3 65 plug connection 3-pole P+E (IP65) J = Junior Timer radial plug connection (IP 65) JR = Junior Timer radial plug connection (with quenching diode, IP 65) U = Deutsch plug connection DT-P, -pole radial (IP 67/69K) UR = Deutsch plug connection DT-P, -pole radial (with quenching diode, IP 67/69K) without = connection without mating plug Q = only connection G with mating plug 9 Related data sheets Reference (Old no.) Description -P- (i-3) The form-tool hire programme -P-67 -P- -P-5 -P-7 Cavity type AL Coil for solenoid valve, series 36X8/6. Amplifier unit for proportional valves (-channel) PBS - 3A Line-mounting body, type GALA (G 3/ ) info.ch@bucherhydraulics.com www.bucherhydraulics.com 8 by Bucher Hydraulics AG Frutigen, CH-37 Frutigen All rights reserved. Data is provided for the purpose of product description only, and must not be construed as warranted characteristics in the legal sense. The information does not relieve users from the duty of conducting their own evaluations and tests. Because the products are subject to continual improvement, we reserve the right to amend the product specifications contained in this catalogue. Classification: 3.35.3.35.35.3 6/6 -P-585-EN-/.8