FKGALCV - 2-way, pilot shifted, proportional throttle, high capacity
Part Number: FKGALCV
Manufacturer: Sun Hydraulics
This valve is a 2-way, 2 position, proportional throttle. Ports 2 and 3 are normally closed. Pilot pressure at port 1 creates a metering orifice between port 2 and 3 that is proportional to the pressure at 1. The force balance of the flow forces, spring and pilot pressure results in a degree of partial self-compensation as the load pressure changes.
Pressure at port 4 directly opposes pressure at port 1.
- These valves may be pressure compensated by an external, modulating, logic element. Use LR_C-XHN for a bypass circuit or LP_C-XHN for a restrictive circuit.
- The valve provides a degree of self-compensation and may be used as a flow control. To increase the accuracy of flow control, an external, modulating, logic element can be used to maintain a constant flow over a wider range of flows and pressures. See performance curves for additional information.
- Ports 1 and 4 should be limited to 500 psi (35 bar).
- Pressure at port 4 directly opposes pressure at port 1.
- An optional tuning adjustment (L control) is offered to vary the pilot pressure required to control flow. The tuning adjustment provides a means to manually increase or decrease flow at a given pilot pressure. The adjustment range is 50 - 250 psi (3,5 - 15 bar), 100 psi (7 bar) Standard Setting.
- Accurate pressure compensated control requires that a constant pressure differential be maintained across the valve.
- 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||30 gpm120 L/min.|
|Maximum Operating Pressure||5000 psi350 bar|
|Maximum Valve Leakage at 110 SUS (24 cSt)||4 in³/min.@1000 psi65 cc/min.@70 bar|
|Pilot Volume Displacement||.10 in³1,6 cc|
|Minimum Pilot Pressure to Operate||100 psi7 bar|
|Hysteresis||± 2 %± 2 %|
|Adjustment - Number of Clockwise Turns to Increase Setting||55|
|Valve Hex Size||1 1/4 in.31,8 mm|
|Valve Installation Torque||150 - 160 lbf ft203 - 217 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|
|Seal kit - Cartridge||Viton: 990-023-006|
|What happens if I block the bypass port on a priority flow control?||The valve acts as a 2 port restrictive flow control.|
|How big is a drop of hydraulic oil?||There are exactly 250 Sun drops in a cubic inch or 15 in a cc.|
|How accurate are Sun's flow controls?||We claim +/- 10%. We set to +/- 5% in production testing to allow for differences in customers' conditions. If you want accuracy, stay in the bottom 2/3rds of the range. Our 12 gpm (45 L/min.) flow controls are quite flat at 9 gpm (34 L/min.) and dead flat below 6 gpm (23 L/min.), until you get to the bottom of the range. Below about .25 gpm (1 L/min.), spool leakage and orifice conditions start to limit accuracy.|
|I have a heat problem, will Sun's priority flow control help?||I am afraid not. Unless you are overflowing your current valve and correctly size ours, you are not likely to notice any improvement. Priority flow controls are not efficient devices. They are an easy way to get more than 1 source of oil from 1 pump but they can generate a lot of heat. Try to size your actuators so the pressures are similar on both the priority and the bypass circuits. If you can't do that, try to have the lower flow leg be the lower pressure. The pump pressure is determined by whichever leg is higher and if there is flow that is taking a pressure drop that is not doing work it is creating heat.|
|What happens if I block the control flow (priority) port?||All flow is blocked, hence the term priority. The priority flow has to be satisfied.|
|What is the compensating pressure of Sun's flow controls?||The spring force in our flow controls equates to about 100 psi (7 bar). This is high enough to give the valves acceptable capacity (not really) and not too high for proper circuit operation. 100 psi (7 bar) is the spring force; at the upper end of the flow control's range, the drop through the valve will be as high as 250 psi (17 bar) before it starts modulating.|
|What is the pressure drop through a flow control?||In a meter-in flow control circuit if the pump is set at 3000 psi and the load is 2000 psi the drop through the flow control is 1000 psi. In a meter-out circuit with the load at 2000 psi the drop through the flow control is 2000 psi.|