PRA-08W-2C-Y-Z Winner Hydraulics: Inverse Proportional Pilot Relief Valve for 08W-2 Cavity
The Winner Hydraulics PRA-08W-2C-Y-Z is the 08W-2 cavity version of Winner’s inverse direct-acting, poppet-type proportional pilot relief valve. It has a 3/4″-16UNF-2A thread and a compact 16 mm tube with an EC-16B coil. It holds its highest pressure setting when no command is applied, and reduces the setting in proportion as coil current increases. With a 350 bar rating and 1 L/min rated pilot flow (2 L/min maximum), it is designed for manifolds and main stages built around the W-series 08W-2 pilot cavity.
Operating Principle
The poppet is spring-biased closed to the top of the selected range. It opens, allowing flow from port 1 to port 2, when port 1 pressure exceeds the spring force minus the solenoid force set by the analog command signal. Higher current lowers the relief pressure proportionally, and with zero current the valve returns to its maximum setting. Back pressure at port 2 (tank) adds directly to the setting at a 1:1 ratio.
PRA-08W-2C-Y-Z Technical Data
| Parameter | Value |
|---|---|
| Valve type | Inverse direct-acting, poppet-type, pilot capacity proportional relief valve |
| Function | High pressure setting with no command |
| Cavity | 08W-2 |
| Thread | 3/4″-16UNF-2A |
| Rated flow | 1 L/min (0.26 gpm) |
| Maximum flow | 2 L/min (0.53 gpm) |
| Max. operating pressure | 350 bar (5000 psi) |
| Valve hex size | 22.22 mm (7/8 in) |
| Installation torque | 25–35 Nm (18–26 lbf-ft) |
| Max. leakage at reseat | Approx. 25 cc/min |
| Reseat | Exceeds 85% of cracking pressure |
| Hysteresis | < 8% with DC input; < 4% with dither |
| Linearity with dither | < 2% |
| Recommended dither | 100–250 Hz (best 140–200 Hz) |
| Coil | EC-16B, 26 W, 16 mm tube (ordered separately) |
| Weight | Approx. 0.19 kg (without coil) |
Pressure Range and Option Codes
| Code | Selection | Factory default (at 0.4 L/min) |
|---|---|---|
| Y = W | 350–210 bar | 210–215 bar |
| Y = A | 210–105 bar | 140–145 bar |
| Y = B | 105–55 bar | 70–75 bar |
| Y = D | 55–20 bar | 28–30 bar |
| Z = L | Standard type, leakproof hex socket adjustment screw | – |
Winner bases its factory setting on the RV-11A main valve. For a specific setting, state your required pressure and the main valve it will pilot when you order.
Product Highlights
- Fits the 08W-2 cavity with a 3/4″-16UNF-2A thread
- High pressure with no command: the setting drops as current rises
- Compact 16 mm tube with a 26 W EC-16B coil
- Four adjustment ranges covering 20 to 350 bar
- Continuous-duty rated coil and efficient wet-armature design
- < 4% hysteresis and < 2% linearity with dither
- Heat-treated, high-precision ground working parts
- WINNERcoat® zinc-nickel plating, salt-spray tested to DIN EN ISO 9227 for up to 1000 hours
- Pressure rating tested to NFPA T2.6.1, with 90/90 fatigue rating assurance
- Every valve 100% functionally tested before shipment
- Range of seal kit materials
Winner recommends a current-sensing amplifier with dither for best performance.
Compatible Main Stages with 08W-2 Pilot Cavity
The PRA-08W-2C-Y-Z suits Winner relief main stages ordered with an 08W-2 pilot cavity, such as:
- RP-18A-20-Y-8W: 760 L/min balanced piston relief (Z = 8W option of RP-18A-20-Y-Z)
- RP-18A-20-Y-8W-76: 760 L/min balanced piston relief, -76 variant
Choosing Between the PRA 2C Versions
| Model | Cavity | Thread | Installation torque | Weight (without coil) |
|---|---|---|---|---|
| PRA-08W-2C-Y-Z | 08W-2 | 3/4″-16UNF-2A | 25–35 Nm | 0.19 kg |
| PRA-8A-2C-Y-Z | 8A-2 | M16 x 1.5 | 27–33 Nm | 0.136 kg |
Both use the EC-16B coil and offer the same four pressure ranges. For low pressure at zero current in the 08W-2 cavity, see the standard direct-acting PRB-08W-2C-Y-Z.
Order the PRA-08W-2C-Y-Z Winner Hydraulics
Atlantech Drives supplies genuine Winner Hydraulics proportional valves worldwide, with fast shipping. Give us the pressure range (W, A, B or D), required setting, main valve and coil voltage, and our commercial team will quote the PRA-08W-2C-Y-Z and its EC-16B coil with stock and lead time. Request a quote today.
