20%, accumulator sense, pump unload valve - pilot capacity
Capacity: 46 in³/min.0,75 L/min. |
Cavity: T-11A
Technical Features [ + ]
The accumulator sense, pump unload pilot valve is used to sense pressure in an accumulator at port 1 of the valve and when the pressure at port 1 reaches the valve setting, port 2 connects to port 3 to vent a relief valve and unload the pump. This valve has a 20% ratio between unload setting and reset; when pressure at port 1 falls below 80% of the valve setting, port 2 is blocked from port 3 and the pump will come back online to recharge the accumulator.
This valve requires a separate check valve between port 1 and the pump. Another version of the accumulator sense, pump unload valve, QCDB, includes a free-flow check valve for pump flows under 12 gpm (50 L/min).
- The pressure differential between unload and reset will be within +3/-2% of the stated ratio of the valve.
- The accumulator sensing area is positively sealed.
- The spool design of this valve allows it to maintain a fixed differential ratio because the areas are created by diameters on the spool that will not wear or change with use.
- Minimum clearances between the spool and sleeve and a seal on the pilot piston diameter significantly reduce the potential for silting.
- When applying this cartridge, a separate drain line is required to prevent erratic operation caused by tank line pressure fluctuations.
- NOTE: Careful consideration should be given when selecting an adjustment range. System pressure drops and flows tend to affect the operation of unloading valves. Low operating pressures combined with low differentials result in a very narrow band between unload and reset, requiring precise system design. High flow rates typically mean high pressure drops, which subtract from the differential the valve has to work with.
- Sun has designed a variety of standard accumulator/pump unload assemblies with a variety of features. These assemblies can be found on our website under SOLUTIONS: ACCUMLATOR SENSE, PUMP UNLOAD.
- 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.
Technical Data [ + ]
Note: Data may vary by configuration. See CONFIGURATION section.
Cavity | T-11A |
Series | 1 |
Capacity | 46 in³/min.0,75 L/min. |
Maximum Operating Pressure | 5000 psi350 bar |
Pilot Flow Capacity | 46 in³/min.0,75 L/min. |
Adjustment - No. of CW Turns from Min. to Max. setting | 55 |
Valve Hex Size | 7/8 in.22,2 mm |
Valve Installation Torque | 30 - 35 lbf ft41 - 47 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 | .35 lb0,15 kg |
Seal kit - Cartridge | Buna: 990011007 |
Seal kit - Cartridge | Polyurethane: 990011002 |
Seal kit - Cartridge | Viton: 990011006 |
Performance Curves [ + ]
FAQs [ + ]
There are exactly 250 Sun drops in a cubic inch or 15 in a cc.
See our Highlight on Accumulator Sense, Pump Unload Valves for detailed information.
Only external seals are serviceable. Sun offers replacement seal kits for all cartridge models. The applicable kit part number can be found in the product page's Technical Data table or by using our Cartridge Seal Kit search function located under Accessories. Please note: Converting the external seals from one material to another does not ensure fluid compatibility with that material due to the existence of internal seals within the cartridge.
Additional Resources [ + ]
Highlights
- Sun Cartridges with EPDM Seals
- CavitySaver multi-function valves deliver single-cartridge solutions
- Sun Expands Corrosion-Resistant Solutions
- QuickDesign with SmartConnect Offers Drag-and-Drop Schematic Tool
- Accumulator Sense, Pump Unload Valves
- Sun's New FLeX Series Solenoid Valves & Coils
- Sun Offers Zinc-Nickel Plating for Corrosion Resistance
Technical Tips
- Manufacturing Sun Cartridge Cavities (522.27 KB)
- Circuit Savers (466.24 KB)
Technical Information