Ventable, pilot-operated, balanced-poppet relief cartridges are normally closed pressure regulating valves. When the pressure at the inlet (port 1) reaches the valve setting, the valve starts to open to tank (port 2), throttling flow to regulate the pressure. They provide a vent port (port 3) that connects between the main piston and pilot stage to provide for remote control by other pilot or 2-way valves. These valves are accurate, have low pressure rise vs. flow, they are smooth and quiet, and are moderately fast.
- Because the modulating occurs inside the cartridge, these valves are immune to most of the problems associated with cavitation, namely noise and manifold erosion.
- Suitable for use in load holding applications, providing that any valving on the vent port (port 3) is zero leak.
- 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.
- Valve is relatively insensitive to varying oil temperatures and oil borne contamination.
- Main stage orifice is protected by a 150 micron stainless steel screen.
- Back pressure on the tank port (port 2) is directly additive to the valve setting at a 1:1 ratio.
- 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||25 gpm95 L/min.|
|Factory Pressure Settings Established at||4 gpm15 L/min.|
|Maximum Operating Pressure||5000 psi350 bar|
|Control Pilot Flow||15 - 20 in³/min.0,25 - 0,33 L/min.|
|Response Time - Typical||2 ms2 ms|
|Maximum Valve Leakage at Reseat||10 drops/min.0,7 cc/min.|
|Adjustment - Number of Clockwise Turns to Increase Setting||55|
|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|
|Model Weight||1.60 lb0,70 kg|
|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.|