Ventable, pilot-operated, anti shock relief cartridges limit maximum system pressure and also limit the rate of pressure rise. The valve opens and then ramps closed at a constant speed, independent of settings and flows. These 3 port valves include a vent port (port 3) that connects between the main piston and the pilot stage to provide for remote control by other pilot or 2-way valves. The adjust screw determines the maximum (relief) setting and the minimum (threshold) setting.
- Because the modulating occurs inside the cartridge, these valves are immune to most of the problems associated with cavitation, namely noise and manifold erosion.
- Will accept maximum pressure at port 2; suitable for use in cross port relief circuits.
- A remote pilot relief on port 3 (vent) will control the valve below its own setting.
- Not suitable for use in load holding applications.
- When pressure at the inlet (port 1) exceeds the threshold setting, the valve opens to tank (port 2). The pilot section moves forward at a steady rate, increasing the setting by compressing the pilot spring. Maximum setting is achieved when the pilot section reaches a mechanical stop.
- Valve provides protection for hydrostatic drives by reducing the jerk caused by sudden reversals. The valve is suitable for cross-port applications.
- When used with a switching device, the valve can provide the ramp characteristic typically provided by proportional valves.
- Small power units can be started against an anti shock relief to provide longer pump life.
- Back pressure on the tank port (port 2) is directly additive to the valve setting at a 1:1 ratio.
- The main stage orifice is protected against contamination.
- Incorporates the Sun floating style construction to minimize the possibility of internal parts binding due to excessive installation torque and/or cavity/cartridge machining variations.
|Capacity||30 gpm120 L/min.|
|Factory Pressure Settings Established at||4 gpm15 L/min.|
|Maximum Operating Pressure||5000 psi350 bar|
|Control Pilot Flow||10 - 25 in³/min.0,16 - 0,41 L/min.|
|Response Time - Typical||2 ms2 ms|
|U.S. Patent #||6,039,0706,039,070|
|Pressure Ramp Up Time||200 - 400 ms200 - 400 ms|
|Adjustment - Number of Clockwise Turns to Increase Setting||4.54.5|
|Valve Hex Size||1 1/8 in.28,6 mm|
|Valve Installation Torque||45 - 50 lbf ft61 - 68 Nm|
|Adjustment Screw Internal Hex Size||5/32 in.4 mm|
|Locknut Hex Size||9/16 in.15 mm|
|Locknut Torque||80 - 90 lbf in.9 - 10 Nm|
|Seal kit - Cartridge||Viton: 990-402-006|
|Where would I use a kick-down relief?||One graphic example is on a portable grain auger for silos. When the farmer gets caught in the auger the kick-down relief trips and allows him to escape.|
|What are the tolerances on pressure settings for Sun's pressure control valves?||Pressure setting tolerances are listed in our Performance Data page. A link to this page can also be found in the Additional Resources tab of the applicable product page.|
|How big is a drop of hydraulic oil? ||There are exactly 250 Sun drops in a cubic inch or 15 in a cc.|
|Can I use a kick-down relief for my system relief?||Maybe not. We build in a good amount of overlap in the kick-down reliefs to prevent false tripping. This means they are not as fast as our standard pilot-operated reliefs. A direct-acting relief valve set just above the kick-down relief valve would be good insurance.|
|Direct acting or pilot operated - what do I use?||Direct-acting valves are used to prevent over pressure, and pilot-operated valves are used to regulate pressure. If you are unsure, use a direct-acting valve. Sun's direct acting valves are very fast, dirt tolerant, stable, and robust. Sun's pilot-operated valves are moderately fast, they have a low pressure rise vs. flow curve, and they are easy to adjust.|
- Patents are pending for this product.