SUN HYDRAULICS
XQCFLANDC

$642.80 USD

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SUN HYDRAULICS
Material:XQCFLANDC
Model:XQCF-LAN-DC
Summary:Y-assembly

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 XQCFLANDC (XQCFLANDC) is a versatile valve assembly engineered to efficiently charge an accumulator using a fixed displacement pump. Designed to optimize hydraulic system efficiency, this assembly automatically unloads the pump when the pressure reaches a predetermined set point and re-engages it when the pressure falls to a specified level determined by the pilot valve's fixed percentage. This dual-functioning ventable relief acts both as a main stage for unloading the pump and as an overpressure relief for the system. An additional circuit feature softens the pump's unloading process, enhancing operational smoothness. To ensure optimal performance, it is crucial to incorporate a separate drain line, preventing erratic operation due to tank line pressure fluctuations. Selecting an appropriate adjustment range is vital, as low operating pressures combined with low differentials can create narrow bands between unload and reset points, necessitating precise system design. High flow rates may result in significant pressure drops, affecting the valve's differential capabilities. The assembly's porting is intentionally large relative to its capacity to encourage using larger piping, minimizing issues from flow-induced pressure drops. The pilot valve's spool design maintains a consistent differential ratio due to non-wearing spool diameters. It's essential that the accumulator pilot valve is set below any reliefs on the pump side of the system to prevent excessive heating. This package includes an overpressure relief device set higher than any pilot valve setting and capped for safety. With a capacity of 10 gpm (40 L/min), this line mount body type requires two mounting holes with specific dimensions for secure installation.

Description

This valve assembly is meant to charge an accumulator using a fixed displacement pump. When the pressure reaches the set point of the valve, the pump is unloaded. When the pressure drops to the value determined by the fixed percentage of the pilot valve, the pump is brought back on line to recharge the accumulator. The ventable relief serves a dual purpose as a main stage to unload the pump and as a system over-pressure relief. The assembly has an additional feature; a simple circuit that softens the unloading of the pump.

When applying this assembly, 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.
The pressure setting and the resultant reseat pressure are in reference to the port 2 area of the QCD* pilot valve. Pump pressure will be higher and accumulator pressure will be lower due to pressure drop caused by flow.
The porting on this assembly is large in relation to its capacity. This is done to encourage the use of correspondingly large piping to minimize problems caused by flow induced pressure drop.
The spool design of the pilot 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.
The accumulator pilot valve must be set below any reliefs in the pump side of the system or severe heating could occur.
The relief in this package is meant to be an over-pressure device. It is set higher than the highest setting of the pilot valve and capped.

Capacity	10 gpm40 L/min.
Body Type	Line mountLine mount
Mounting Hole Diameter	.41 in.10,4 mm
Mounting Hole Depth	ThroughThrough
Mounting Hole Quantity	22

Show FAQ

How big is a drop of hydraulic oil?	There are exactly 250 Sun drops in a cubic inch or 15 in a cc.
Why does Sun use 6061 aluminum?	6061-T651 is relatively strong, relatively inexpensive, difficult to machine, readily available in all shapes and sizes and very corrosion resistant. 2024 is stronger and machines beautifully, but is expensive and falls to pieces in a corrosive environment.
Why doesn't Sun anodize their aluminum bodies?	Reasons to anodize: To increase corrosion resistance. Sun uses 6061-T651 aluminum. It is one of the most corrosion resistant aluminum alloys there is. Whether or not anodizing improves the corrosion resistance of 6061 aluminum is debatable. We have yet to have a manifold returned because of corrosion. Appearance (color). The 2 colors that would appeal to Sun would be blue or black. Unfortunately these are the colors that are hardest to do consistently. To provide a hard wear surface. Sun does not make parts-in-body valves. The manifold is just plumbing. We don't need a wear surface. Because everyone else does it. Bad reason. Reasons to not anodize: Cost. It's another process. Logistics. When you make tens of thousands of manifolds a month and you anodize hundreds, it's a problem. Consistency. See above. Stamping. After a body is anodized you cannot do any more stamping without making a mess.Inspection. Have you ever tried to look for burrs in a black anodized body? It's the old blackboard factory at night scenario. Torque. You will experience an increase in breakaway torque when removing items from an anodized manifold. Fatigue life. This is the best reason to not anodize. Fatigue failure is a very complex phenomenon. What it takes to initiate a crack is difficult to predict. What it takes to propagate a crack is readily defined. Anodizing produces a very thin, very hard, and very brittle surface on aluminum. The first time you pressurize an anodized aluminum manifold you have initiated fatigue cracks. Whether or not the stress is enough to propagate the cracks is a matter of pressure and manifold geometry. Anodizing an aluminum manifold grossly reduces the fatigue life by anywhere from 20% to 50%.
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.

Additional Resources

Notes:

Important: Carefully consider the maximum system pressure. The pressure rating of the manifold is dependent on the manifold material, with the port type/size a secondary consideration. Manifolds constructed of aluminum are not rated for pressures higher than 3000 psi (210 bar), regardless of the port type/size specified.

SUN HYDRAULICSXQCFLANDC

Additional Resources

SUN HYDRAULICS
XQCFLANDC