SUN HYDRAULICS
RDDTQBN

$180.09 USD

SUN HYDRAULICS
Material:RDDTQBN
Summary:Cartridge

Quantity in stock: 0

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***Disclaimer: The following summary contains information gathered from various sources such as product descriptions, technical specifications and catalogs. While efforts have been made to provide accurate details, inaccuracies may occur. It is advised to verify all information by contacting Sun Hydraulics directly.***
The Sun Hydraulics RDDTQBN (RDDTQBN) is a direct-acting relief cartridge designed to safeguard hydraulic components from pressure transients. This normally closed, pressure-limiting valve activates when the inlet port pressure reaches the set threshold, opening to the tank port and throttling flow to prevent a pressure rise. Notable for its smooth and quiet operation, this valve is virtually leak-free, dirt tolerant, and resistant to silting. It responds rapidly with a typical response time of 2 ms. The RDDTQBN is CE marked as per the European Directive for Pressurized Devices (PED 97/23/EC), ensuring it meets critical safety standards. The valve's setting represents the excess operating pressure at which it opens, with approved flow rates indicated on its performance curve. It can handle maximum pressures of up to 422 bar and is ideal for applications requiring load holding capabilities or cross-port relief circuits. The design incorporates Sun's floating style construction to minimize internal binding risks due to installation torque or machining variations. The valve's capacity is 19.8 gpm (75 L/min), and it has a maximum leakage rate of 10 drops/min at reseat conditions, which occur at 90% of the set pressure. The RDDTQBN is relatively unaffected by changes in oil temperature or contamination levels, making it suitable for diverse hydraulic systems. It features various adjustment ranges from 100 bar to 330 bar, with other settings available upon request. Installation requires specific torques: a valve installation torque of 30-35 lbf ft (41-47 Nm) and a locknut torque of 80-90 lbf in (9-10 Nm). This robust cartridge weighs .30 lb (.15 kg) and uses Viton seals for enhanced durability.

Description

Direct-acting relief cartridges are normally closed, pressure-limiting valves used to protect hydraulic components from pressure transients. When the pressure at the inlet (port 1) reaches the valve setting, the valve starts to open to tank (port 2), throttling flow to limit the pressure rise. These valves are smooth and quiet, essentially zero leak, dirt tolerant, immune to silting and are very fast. The CE marked valve is a safety valve that meets the requirements of the European Directive for Pressurized Devices (PED) 97/23/EC. The valve setting represents the excess operating pressure at which the valve opens. Valve capacity can be determined from the performance curve. It shows an approved flow which depends on the excess operating pressure. As a requirement of the PED, the system pressure at the maximum approved flow is a maximum of 10% above the excess operating pressure.

Standard settings for preset valves include:
- A adjustment range: 100 bar, 140 bar, 160 bar and 210 bar
- W adjustment range: 250 bar
- C adjustment range: 330 bar
Other settings are available upon request.
At this time RDDT and RDFT are the only Sun relief valves that are CE marked.
Each delivery contains a TÜV-Approval, which is a certification of the excess operating pressure and the approved flow, an EC Declaration of conformity and an instructional manual.
Pressure settings from 90 bar up to 422 bar are approved and certified by TÜV
Will accept maximum pressure at port 2; suitable for use in cross port relief circuits.
Valve is relatively insensitive to varying oil temperatures and oil borne contamination.
Suitable for use in load holding applications.
Back pressure on the tank port (port 2) is directly additive to the valve setting at a 1:1 ratio.
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.

Cavity	T-10A
Series	1
Capacity	19.8 gpm75 L/min.
Response Time - Typical	2 ms2 ms
Maximum Valve Leakage at Reseat	10 drops/min.0,7 cc/min.
Reseat	>90% of setting>90% of setting
Adjustment - Number of Clockwise Turns to Increase Setting	55
Valve Hex Size	7/8 in.22,2 mm
Valve Installation Torque	30 - 35 lbf ft41 - 47 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
Model Weight	.30 lb0,15 kg
Seal kit - Cartridge	Viton: 990-310-006

Show FAQ

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.
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.

SUN HYDRAULICSRDDTQBN

Additional Resources

SUN HYDRAULICS
RDDTQBN