SUN HYDRAULICS CORP
RBARDWN
Pressure Control

Two-port, pilot-stage, air-controlled, direct-acting relief cartridges are normally closed pressure regulating valves. When the pressure at port 1 (inlet) is sufficient to overcome the force due to the air signal, a flow path is opened from port 1 to port 2 (tank). These cartridges are designed for pilot flow applications and utilize Sun's T-8A cavity so they can be used in conjunction with Sun's pilot-operated, main-stage valves.

• Utilizes the Sun T-8A 2-port cavity making it the ideal choice to use in conjunction with Sun's main stage pilot or vent-to-operate cartridges. Separate pilot lines are eliminated and only one cavity needs to be machined to accommodate both the control and primary function. Note: All 2-position, 2-way pilot stage control cartridges utilize the same cavity and are physically interchangeable. Functionality is the only consideration.
• Note: The main stage valve should first be installed to the correct torque value followed by the T-8A pilot control section into the main stage valve to its required torque value.
• Different pilot control port options are available. See Option Selection for details.
• Ports 1 and 2 may be pressured to 5000 psi (350 bar).
• Hardened poppet and seat provide consistent operation, low leakage rates and superior wear characteristics.
• Two different oil-to-air pilot ratios are available; 50:1 and 75:1. See Option Selection.
• Maximum pilot control port pressure is 200 psi (14 bar).
• Backpressure at port 2 increases the relief setting by a .43 multiplier.
• 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.

Additional Resources

• CE/TÜV Certified Pressure Relief Valves
• Pressure Relief and Regulating Cartridge Valve Technical Tips
• Pilot Operated, Balanced Poppet Relief Valves
• Sun Expands Corrosion-Resistant Solutions
• Sun Offers Zinc-Nickel Plating for Corrosion Resistance
• Sun Cartridges with EPDM Seals
• Series 4 PLUS Cartridges Offer Higher Flows with Lower Pressure Losses
• 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
• Manufacturing Sun Cartridge Cavities
• Pressure Relief and Regulating Valves
• Sun Model Code Explanation; 999-901-334
• Cartridges: Materials of Construction
• Fluid and Temperature Recommendations
• Performance Data
• Sun's Floating Style Screw-In Cartridge
• Units of Measure, Settings, and Conversions
• Cavity Information (S-171) and Tooling