Ventable, pilot-operated, balanced poppet relief valve
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.|
|Maximum Valve Leakage at Reseat||10 drops/min.0,7 cc/min.|
|Response Time - Typical||2 ms2 ms|
|Adjustment - No. of CW Turns from Min. to Max. 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||Buna: 990402007|
|Seal kit - Cartridge||Polyurethane: 990002002|
|Seal kit - Cartridge||Viton: 990402006|
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.
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.
There are exactly 250 Sun drops in a cubic inch or 15 in a cc.
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 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.
- CE/TÜV Certified Pressure Relief Valves
- Sun's New FLeX Series Solenoid Valves & Coils
- Pressure Relief and Regulating Cartridge Valve Technical Tips
- Pilot-Operated, Balanced Poppet Relief Valves
- Get the relief you need. Adjustable. Ventable. Blockable. FLeX-ible.
- Sun Offers Zinc-Nickel Plating for Corrosion Resistance
- Sun Cartridges with EPDM Seals
- Sun Expands Corrosion-Resistant Solutions
- Precise electro-proportional inverse relief valve
- Pilot-Operated, Balanced Poppet, Anti Shock Reliefs
- CavitySaver multi-function valves deliver single-cartridge solutions
- 'Soft' Relief Eliminates Pressure Spikes
- Tri-Grip Handknob Now Offered From Sun as a Standard Control Option
- QuickDesign with SmartConnect Offers Drag-and-Drop Schematic Tool
- Sun Introduces 'Hybrid' Valves
- Cavity Information (S-171) and Tooling
- Sun Model Code Explanation; 999-901-334 (343.9 KB)
- Cartridges: Materials of Construction
- Fluid Recommendations: Oil Viscosity, Cleanliness & Temperature
- Performance Data
- Sun's Floating Style Screw-In Cartridge (1.06 MB)
- Units of Measure, Settings, and Conversions
- Pressure Equipment Directive 2014/68/EU