rvck | Cartridges » Pressure Control » Relief

This FLeX Series solenoid-operated, 2-stage, balanced relief cartridge is a pressure regulating valve.

The valve is normally vented. When vented (de-energized), the pressure drop from the inlet (port 1) to tank (port 2) is typically 100 psi (see performance curves).

Energizing the solenoid activates the relief function. In relief mode, the valve opens to tank (port 2), throttling flow to regulate the pressure when the pressure at the inlet (port 1) reaches the valve setting. The setting is adjustable with an adjust screw.

Cartridges configured with EPDM seals are for use in systems with phosphate ester fluids. Exposure to petroleum based fluids, greases and lubricants will damage the seals.
Designed and tested to 10-million operational cycles at full-rated pressure.
Exceeds new NFPA test standard T2.6.1 R2014 for fatigue and burst pressure ratings.
Higher flow rates than competing valves of similar size.
All configurations of this valve include zinc-nickel plating as standard for 1000-hour salt fog protection.
Coil connector options offer ratings up to IP69K. See individual coil product pages for details.
This cartridge utilizes both 740 Series high-power and 747 Series hazardous location coils.
Back pressure on the tank port (port 2) is directly additive to the valve setting at a 1:1 ratio.
Main stage orifice is protected by a 150-micron stainless steel screen.
Will accept maximum pressure at port 2.
All configurations of this valve are assembled with a non-removable adjust screw.
FLeX Series relief valves are fully compatible with the XMD Expandable Mobile Drivers from Sun.
A FULL DATA SHEET is available for this model using the link at the top of the page.
A wide variety of coil termination and voltage options are available, with and without surge protection. See the CONFIGURATION section.
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.

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Note: Data may vary by configuration. See CONFIGURATION section.

Cavity	T-10A
Series	1
Capacity	25 gpm95 L/min.
Maximum Operating Pressure	5000 psi350 bar
Factory Pressure Settings Established at	4 gpm15 L/min.
Maximum Valve Leakage at 110 SUS (24 cSt)	5 in³/min.@2000 psi80 cc/min.@140 bar
Response Time - Typical	50 ms50 ms
Response Time - Typical (Relief)	10 ms10 ms
Adjustment - No. of CW Turns from Min. to Max. setting	3.53.5
Valve Hex Size	7/8 in.22,2 mm
Valve Installation Torque	30 - 35 lbf ft41 - 47 Nm
Adjustment Screw Internal Hex Size	1/8 in.3,2 mm
Locknut Hex Size	7/16 in.11,1 mm
Locknut Torque	45 - 55 lbf in.5 - 6 Nm
Model Weight	.40 lb0,20 kg
U.S. Patent #	10,533,58410,533,584
Seal kit - Cartridge	Buna: 990010007
Seal kit - Cartridge	Polyurethane: 990010002
Seal kit - Cartridge	Viton: 990010006

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Performance Curve for RVCK: FLeX Series 2-stage, solenoid-operated adjustable relief valve, normally vented

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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.

Where would I use a kick-down relief?

One graphic example is on a portable grain auger for silos. When the farmer gets caught in the auger the kick-down relief trips and allows him to escape.

What are the tolerances on pressure settings for Sun's pressure control valves?

Pressure setting tolerances are listed in our Performance Data page. A link to this page can also be found in the Additional Resources tab of the applicable product page.

How big is a drop of hydraulic oil?

There are exactly 250 Sun drops in a cubic inch or 15 in a cc.

Can I use a kick-down relief for my system relief?

Maybe not. We build in a good amount of overlap in the kick-down reliefs to prevent false tripping. This means they are not as fast as our standard pilot-operated reliefs. A direct-acting relief valve set just above the kick-down relief valve would be good insurance.

What is the difference between nominal and maximum flow capacity?

Nominal flow capacity is based on performance limits. Maximum flow capacity is based on pressure drop. When selecting any direct-acting solenoid valve, first check the performance limits plot, then check if pressure drop is acceptable.

What parts of the Sun cartridge valve are field serviceable?

Only external seals are serviceable. Sun offers replacement seal kits for all cartridge models. The applicable kit part number can be found in the product page's Technical Data table or by using our Cartridge Seal Kit search function located under Accessories. Please note: Converting the external seals from one material to another does not ensure fluid compatibility with that material due to the existence of internal seals within the cartridge.

Is the FLeX program available in QuickDesign SmartConnect?

Yes. All FLeX phase 1 valves are available in the SmartConnect schematic tool, and are also available for submittal to QuickDesign.

Do FLeX valves utilize a floating nose design?

Yes. All FLeX valves utilize the Sun floating nose design.

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Highlights