Assembly Build Process

Sun's Assembly Build Process allows you to configure a cartridge and manifold, or main stage and pilot stage cartridge, and build a digital assembly in three dimensional space. The resulting output of this process is the assembly product page, including configuration-specific images, symbols, product information and CAD files for download.

The Assembly Build Process can be accessed from either a cartridge or manifold product page. Only valid choices are allowed.

From a manifold page, you must first choose your cartridge function. Once you choose your function, click on the BUILD ASSEMBLY button below the WHERE TO BUY BUTTON. Once clicked, you will be presented with valid cartridges for your manifold. Select the cartridge of your choice and follow the instructions at the top of the page. If your particular combination has been generated before, the resulting assembly page will be available immediately. If not, you will be asked to enter your email address. Once the page is complete, an email will be sent to you including a link to the assembly product page.

From a cartridge product page, click on BUILD ASSEMBLY and you will be presented with a listing of compatible manifolds. In the case of main stage and pilot stage cartridges, you can either build a cartridge to cartridge assembly or a cartridge to manifold assembly. Once your choice has been made, follow the instructions at the top of the page. If your particular combination has been generated before, the resulting assembly page will be available immediately. If not, you will be asked to enter your email address. Once the page is complete, an email will be sent to you including a link to the assembly product page.

Please note that the Assembly Build Process is an automated process. It can be utilized at any time. Pages are generated typically within minutes but delays can occasionally be expected. In the event of a delay, a team at Sun will work to resolve the issue to ensure you receive your information as quickly as possible.

Bi-directional direct-acting relief valve

Capacity: 30 gpm120 L/min. | Cavity: T-3A

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Technical Features [ + ]

The bi-directional, direct-acting relief cartridge is a normally closed, pressure-limiting valve used to protect hydraulic components from pressure transients. When the pressure differential between ports 1 and 2 exceeds the valve setting, the valve starts to open, throttling flow to limit the pressure rise, regardless of the direction.

Both directions have very similar setting and performance.

Because the modulating occurs inside the cartridge, these valves are immune to most of the problems associated with cavitation, namely noise and manifold erosion.
The seals on the adjust screw are exposed to pressure at port 1 which means this valve can only be adjusted when the pressure is removed or port 2 is used to set the valve. The setting procedure at port 1 is; check the setting, remove the pressure, adjust the valve, check the new setting.
All 2-port relief cartridges (except pilot reliefs) are physically and functionally interchangeable (same flow path, same cavity for a given frame size).
Valve is relatively insensitive to varying oil temperatures and oil borne contamination.
Select a spring range where the desired relief setting is approximately mid-range to high between the minimum and maximum pressure to ensure maximum valve repeatability.
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.

Technical Data [ + ]

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

Cavity	T-3A
Series	2
Capacity	30 gpm120 L/min.
Maximum Operating Pressure	5000 psi350 bar
Factory Pressure Settings Established at	4 gpm15 L/min.
Maximum Valve Leakage at Reseat	30 drops/min.30 drops/min.
Response Time - Typical	2 ms2 ms
Reseat	>85% of setting>85% of setting
Hysteresis	≤ 3 %≤ 3 %
Adjustment - No. of CW Turns from Min. to Max. setting	55
Valve Hex Size	1 1/8 in.28,6 mm
Valve Installation Torque	45 - 50 lbf ft61 - 68 Nm
Seal kit - Cartridge	Buna: 990303007
Seal kit - Cartridge	Polyurethane: 990303002
Seal kit - Cartridge	Viton: 990303006

Performance Curves [ + ]

Performance Curve for RBFA: Bi-directional direct-acting relief valve

FAQs [ + ]

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.

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.

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.

Additional Resources [ + ]

Highlights