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Sun Hydraulics-QPACKDN-QPACKDN

SUN HYDRAULICS
QPACKDN


$183.87 USD
  • SUN HYDRAULICS
  • Material:QPACKDN
  • Model:QPAC-KDN
  • Summary:Cartridge

Quantity in stock: 0

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***Disclaimer: The following summary contains information gathered from various sources such as product descriptions, technical specifications and catalogs. While efforts have been made to provide accurate details, inaccuracies may occur. It is advised to verify all information by contacting Sun Hydraulics directly.***
The Sun Hydraulics QPACKDN (QPACKDN) is an accumulator sense, pump unload pilot valve specifically engineered to monitor pressure in an accumulator at port 1. When the pressure at port 1 reaches the preset valve setting, this valve facilitates the connection of port 2 to port 3 to vent a relief valve and subsequently unload the pump. This model features a notable 30:1 ratio between unload setting and reset; thus, when the pressure drops below 70% of the set value, port 2 is blocked from port 3, allowing the pump to recharge the accumulator. It is essential to incorporate a separate check valve between port 1 and the pump for optimal operation. The QPACKDN requires a separate drain line to prevent erratic operation caused by fluctuations in tank line pressure. This design maintains a fixed differential ratio due to its spool configuration, ensuring durability as it prevents wear or changes over time. The minimum clearances between spool and sleeve, along with a seal on the pilot piston diameter, significantly mitigate silting risks. It operates with a maximum pressure capacity of up to 5000 psi (350 bar) and has a pilot flow capacity of 46 in\u00b3/min (0.75 L/min). For installation, it requires torque settings between 30-35 lbf ft (41-47 Nm), with adjustments made via an internal hex screw size of 5/32 inch (4 mm). The overall weight of this model is approximately .35 lb (0.15 kg), making it lightweight yet robust for demanding applications requiring precise control over hydraulic systems.

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 30% ratio between unload setting and reset; when pressure at port 1 falls below 70% 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, QCDC, 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 +/- 1% of the stated ratio of the valve with up to an additional 25 psi (1,7 bar) due to dynamic seal friction.
  • 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.
CavityT-11A
Series1
Capacity46 in³/min.0,75 L/min.
Maximum Operating Pressure5000 psi350 bar
Pilot Flow Capacity46 in³/min.0,75 L/min.
Adjustment - Number of Clockwise Turns to Increase Setting55
Valve Hex Size7/8 in.22,2 mm
Valve Installation Torque30 - 35 lbf ft41 - 47 Nm
Adjustment Screw Internal Hex Size5/32 in.4 mm
Locknut Hex Size9/16 in.15 mm
Locknut Torque80 - 90 lbf in.9 - 10 Nm
Model Weight.35 lb0,15 kg
Seal kit - CartridgeViton: 990-011-006

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