Load control valves
Eaton offers a broad range of Vickers load control valving including counterbalance, motion control and pilot operated check valves. The prime function of load controls is to prevent loads from running ahead of pump supply and/or to provide positive load holding.
These valves provide precise and stable motion control. Load control valves are ideally suited for moving and positioning systems.
These products include both threaded cartridge and inline housing valves to meet the majority of load control requirements.
Load control application tips 3-ported counterbalance valve
These valves are used with an open center on/off directional valve for:
• Precise control of overrunning loads
• Protection from pump cavitation
• Preventing actuator from running ahead of the pump supply and
• Providing load holding and hose failure safety
Vented (4-ported) counterbalance valves
These valves are used for:
• Precise control of overrunning loads
• Regenerative cylinder circuits
• Meter-out control and providing load holding and hose failure safety with proportional control valve
Pilot operated check valves
These valves are used:
• For position load locking
• As an alternative to counterbalance valves where neither the overrunning loads or release speed are factors in the application.
• Pilot operated check valves are covered in section G
Counterbalance cartridges, 3-ported
The CBV are single cartridge type counterbalance valves that have:
• A check feature allowing free flow in one direction
• A relief feature controlling flow in the other direction
• A pilot signal that overrides the relief setting providing the counterbalance function.
The CBV*-10 series products are capable of handling flows to up 60 L/min (15 USgpm) and pressures up to 350 bar (5000 psi).
The CBV*-12 series products are capable of handling flows up to 114 L/min (30 USgpm) and pressures up to 350 bar (5000 psi).
These valves are available with 4:1 and 10:1 pilot ratios. As a general rule, a low pilot ratio will provide better motion control and stability in systems with higher capacitance (spongy) and inductance (high inertial loads). A high pilot ratio improves the efficiency of a hydraulic system, but motion control stability may suffer.
The 3-ported counterbalance valves are offered with a wide variety of standard housings with SAE and BSPP port options. Aluminum and steel housings are available in the following styles:
• Inline single
• Inline dual
• Inline dual, with integral shuttle
• SAE 4-bolt, Code 61
• Close coupled, nipple mounted
• Gasket mounted single
• Gasket mounted dual
• Various bolt on manifolds for Eaton hydraulic motor
Vented counterbalance cartridges, 4-ported
The VCB1-10 and VCB1-12 are single cartridge type counterbalance valves that have:
• A check feature that allows free flow in one direction
• A relief feature that controls flow in the other direction and
• A pilot signal that overrides the relief setting, providing the counterbalance function
The additional 4th port on this valve provides an external drain that makes the valve insensitive to back pressure at port 2, when the valve is piloted open.
This is particularly useful in regenerative circuits, meterout circuits, servo valves and proportional valves circuits.
This valve is available with a 4:1 pilot ratio. The 4-ported counterbalance valve is offered with a wide variety of standard housings with SAE and BSPP port options.
NOTE: For applications where the flow rate will not exceed 37,8 L/min (10 USgpm) for VCB1-10 and 95 L/min (25 Usgpm) for VCB1-12, the standard C- **-4 housing can be used.
For applications over those flows or those that require a reduced pressure drop, housings with the slot feature or a C-**-4U cavity are required.
Aluminum and steel housings are available in the following styles:
• Inline single
• Inline dual
• Gasket mounted single
Motion control valves
These are inline housing type motion control or counterbalance valves that utilize separate cartridges to perform the counterbalance function as described in the 3-ported version. The 16 and 20 series valves are available in both single and dual functions. The 16 series is capable of handling flows up to 151 L/min (40 USgpm) and pressures up to 210 bar (3000 psi). The 20 series valves are capable of handling 190 L/min (50 USgpm) and pressures up to 210 bar (3000 psi). Both series offer a 10:1 pilot ratio.
Produs de: Eaton
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