Directional Control Valves

Transcription

1 Frequently sked Questions Frequently sked Questions What is the function of a directional control valve? directional control valve is the extend and retract control for your hydraulic cylinders. It provides a flow path from the pump to the cylinders and a return path from the cylinders to the fluid reservoir. What is the flow pattern for a double acting system? four port valve is normally re quired for double acting systems. Let s look at the two control positions first. In the advance position pressure flows from the pump through the valve from to, flows back to. In the retract position is flowing to, is returned to. You need to be aware that when shifting between po si tions, there is a transitional state. During this transition, there is some cross-talk between ports al low ing pressure to drop in the pres sur ized circuit and return to tank. he importance of this information is that you cannot pres sur ize a system and shift back to the closed center position to hold it clamped. Using the center position to hold is inappropriate because it removes the pump from the circuit and defeats the purpose of a live hy drau lic system. NOE: Maximum system flow rate 1.5 gpm (346.5 cu. in. per minute) for all VektorFlo special function valves. Excess flow voids warranty What is the purpose of the center position? he center position on 3-osition, 4-ort solenoid valves is the resting position with both solenoids de-energized. On manual valves the center position is transitional and is often unused. Closed center solenoid valves are used to assure that no movement takes place upon power failure (though a small amount of pressure will be lost in transition). he closed center manual valve makes no change in circuit direction in the center position. blocked center in either a manual or solenoid valve is commonly used for decoupling of palletized double acting systems. his allows the pressure to be dropped from both the and hoses for disconnect and reconnect under no pressure. In the center position of this valve is blocked,, and are connected. What is the flow pattern for a single acting system? Single acting systems typically have only two valve positions. In the advance position is connected to. In the retract position, is connected to and is blocked, allowing the cylinder springs to push the fluid back to tank. What do I need to watch for when I m plumbing a system? You should watch for proper flow paths among other things. Remember that hydraulic fluid, like water, will take the path of least re sis tance. lan your fluid distribution manifolds and fittings to provide for the smoothest possible flow to and from your cylinders. he best schematically designed control system can be ruined by poor plumbing implementation. I can get a spool valve locally for a lot less money than your valve. Will it work? You are responsible for the appropriate use of all devices. he use of spool valves invalidates the warranty on any VektorFlo pump. If you are using a suitable industrial pump and valve, they may work. he use of spool valves, especially when attempting to use a center (or de-energized) function can cause unusual flows and pressures, resulting in unpredictable actions of clamps. he use of a pump with excess flow invalidates the warranty on any VektorFlo item. If you choose to use non-vektek pumps and valves, you assume the responsibility for selecting appropriate sizes. he use of spool valves invalidates the war ran ty on any VektorFlo ump. ll VektorFlo directional control valves are rated at 5,000 psi working pressure. hey typically incorporate international standard mounting and fluid flow pat terns (NF DO3/ISO 44011). his allows one valve sub-plate to serve as the mounting platform for any of these valves. lumbing lines are connected to ports on the sides of the sub-plate while four hold-down screws secure the top valve. Removal and replacement is easily ac com plished without disturbing system plumbing; greatly reducing chances of system contamination. Valve change overs can be accomplished in minutes, not hours: a tremendous advantage as production downtime costs mount up. Standardized mounting patterns also mean that valve operation can easily be upgraded from manual to electric, again without having to change system plumb ing. Our electric solenoid valves are direct bolt-on replacements for our manually operated versions. VektorFlo DO3 style valves may be positioned in either of two ways: 1. Mounted away from the power source on one of our remote valve subplates(perhaps mounted directly on your fixture or machine tool). 2. Mounted directly on our large capacity power supply using a direct mount sub-plate. his further sim pli fies plumbing and eliminates the need for each individual fixture to have its own valves. -21 N Vektek, pril 2019

2 2-osition, 3-ort Control Valves: 2-osition, 3-ort, DO3 Mount vailable as either manual or solenoid operator. Efficient control solutions for single-acting systems. 2-osition, 3-ort manual valve is equipped with colored bonnet to differentiate it from the 3-osition, 4-ort. Shear style valve de sign features hardened steel poppets in an aluminum body. 2-osition. 3-ort Manual Valve NOE: Maximum system flow rate is 1.5 gpm (346.5 cu. in. per minute) for all VektorFlo special function valves. Excess flow voids warranty. NC NO DIN Solenoid Valve Connecter Included N-4 D03 Mounting attern ILS REV H 2-osition, 3-ort Solenoid Valve Function Replacement Valve Connector art * Supplied with rectified connectors that must be used to insure proper valve function and warranty. Use of any other connector will void the valve warranty. Solenoid Voltage ower Consumption (Watts) Normally Open VDC * Normally Open VC Normally Closed VDC * Normally Closed VC 28.6 Duty Rating Vektek, February %

3 Control Valves: 3-osition, 4-ort hese valves offer the features required to efficiently control a double acting workholding system. (hey may also be used to control single acting systems working in opposition.) Valves incorporate extremely low leakage (4 drops per minute per seal) pressure balanced shear type seals and poppet designs. Heat treated rotor and poppets are spring and pressure loaded against each other to provide positive fluid control for hundreds of thousands of cycles Operates with rotary handle motion using an anti-friction rotary bearing. Detented internal rotor snaps into position ensuring accurate alignment of internal flow passages. ll valves incorporate lightweight aluminum alloy bodies and are furnished with required standard length mounting bolts. DO3 Mount Directional Con trol Valves anel Mount 3-osition, 4-ort Manually Operated Control Valves: 3-osition, 4-ort Manual Valve Configuration Seals Fluid emp. Maximum Fluid Flow Maximum ank ort ressure DO3 Mount Closed Center una 158 F 3 gpm 250 psi max locked Center N eflon* anel Mount Closed Center una 158 F 3 gpm 250 psi max locked Center N eflon* N-5 Manual Valve Handle * Valve ype Kit contains: long and short handles, adapter mounting screw and adapter ILS * Use with manual Valves: , , , , and Vektek, February 2017

4 Valve Subplates NF D03 Standard Contains all plumbing connections for,,, and connections. Simplifies at the fixture valve mounting for 1, 2 or 4 valve plumbing. Makes valve changes simple, just remove four cap screws to change valves. ll VektorFlo valves fit the DO3 pattern except panel mount model #10-24 ap X.50 Deep (X4).160 Locating Hole ressure ort SE 6 uxiliary "" ort (With SE 4 lug) Drilled & C'bored for #10 SHCS (X4) "" ort SE ank ort SE 6 uxiliary "" ort (With SE 4 lug) D03 MOUNING ERN ER NF/3.5.1M R NSI/93.7M-1986 "" ort SE 4 ILS REV E Subplate D03 Valve Mounting Surface Each D03 Mounting Surface.96 SE 4 & orts SE 6 Return ort Each Set of orts 2X X X N-4 2X X X.56 Description wo Valve Manifold Four Valve Manifold SE 4 ort(gauge) ILS SE 6 ressure ort REV F hese subplates are used with the following valves: 2-osition 3-ort Manual Valve osition 3-ort Solenoid Valves osition 4-ort Manual Valves osition 4-ort Solenoid Valves Vektek, pril

5 Valve Subplates Crossover and lanking lates.20 DO3 VLVE MOUNING.20 DO3 VLVE MOUNING CROSSOVER - CROSSOVER ROLL IN LOCOR 1.75 ROLL IN LOCOR CROSSOVER LE LNKING LE ILS REV lates Crossover late lanking late - apping lates N-5 apping late apping late Vektek, pril 2019

6 Directional Con trol Valves 3-osition, 4-ort Solenoid Operated Control Valves 3-osition, 4-ort rovide improved control of clamping circuits with true poppet design. Multiple coil voltages available. Internal design promotes improved service life. Narrow width allows mounting of multiple valves on standard DO3 manifolds. ll valves have built-in -lock check for fail safe multi-valve operation. Coils can be easily replaced. C CC DIN Solenoid Valve Connectors- Included D03 Mounting attern ILS REV N N-6 Control Valves: 3-osition, 4-ort Solenoid Valve Function Replacement Valve Connector art * Supplied with rectified connectors that must be used to insure proper valve function and warranty. Use of any other connector will void the valve warranty. Solenoid Voltage ower Usage (watts) 7I Closed Center VDC I * Closed Center VC I locked Center VDC I * -locked Center VC 28.6 Duty Rating 100% Vektek, February