Product Overview
The SUN Hydraulics PBDB-LNN is a screw-in cartridge style pressure reducing/relieving valve designed for precise secondary circuit pressure control in industrial hydraulic systems. Manufactured by Sun Hydraulics, a globally recognized leader in high-performance cartridge valve technology, this valve operates on a direct-acting, balanced poppet principle. It reduces a higher primary inlet pressure to a constant, lower regulated outlet pressure, while simultaneously providing a relieving function to protect the reduced-pressure circuit from pressure spikes caused by thermal expansion or external load-induced intensification. The PBDB-LNN is a normally open, adjustable pressure reducing valve with a standard “L” adjustment option and “NN” seal configuration, making it a direct-fit solution for demanding manifold-based hydraulic circuits.
Technical Specifications
| Parameter | Specification / Feature |
|---|---|
| Component Type | Hydraulic Valve – Pressure Control Valve (Pressure Reducing / Relieving Cartridge Valve) |
| Model Designation | PBDB-LNN |
| Manufacturer | Sun Hydraulics |
| Operating Pressure | Standard Industrial Grade (Up to 350 bar / 5000 psi rated inlet) |
| Adjustment Style | “L” – Standard Adjustable Screw with Locknut |
| Seal Configuration | “NN” – Buna-N (Nitrile) Seals, Standard Industrial Fluid Compatibility |
| Mounting & Connection | Standard Sun Hydraulics T-11A Cavity, Screw-In Cartridge, ISO 7789 Interface |
| Flow Capacity | Up to 30 L/min (8 gpm) Nominal |
| Pressure Adjustment Range | Standard Range up to 210 bar (3000 psi) Regulated Outlet |
Engineering Features & Advantages
- Precision Pressure Regulation: The direct-acting, balanced poppet design delivers smooth, accurate pressure reduction with minimal hysteresis and excellent repeatability, ensuring stable secondary circuit pressure regardless of inlet pressure fluctuations.
- Integrated Relieving Function: In addition to pressure reduction, the valve relieves excess pressure in the reduced-pressure circuit back to tank, protecting downstream components from thermal expansion and load-induced pressure spikes.
- Industrial Reliability: Built for continuous operation under severe industrial conditions, with hardened, precision-machined internal components that resist wear and contamination-induced failure.
- Direct Fit Replacement: Exact dimensional and functional compatibility with original Sun Hydraulics PBDB-LNN specifications, including the standard T-11A cavity and “L” adjustment style, ensuring drop-in replacement without manifold modification.
- Direct Fit Replacement: Precision-manufactured to original SUN specifications for direct replacement, minimising downtime and eliminating fitment issues.
Typical Industrial Applications
The SUN Hydraulics PBDB-LNN is a screw-in cartridge style pressure reducing/relieving valve designed for precise secondary circuit pressure control in industrial hydraulic systems.
PRODUCT IMAGES



SUN HYDRAULICS PBDB-LNN Pressure Reducing Valve
⚡ Emergency Plant Maintenance & Ready-to-Ship Notice:
- Authentic & Fully Tested: 100% bench tested for hydraulic response, pressure rating, and null-bias stability before dispatch.
- Fast Dispatch: In-stock units ready for same-day dispatch via DHL / FedEx Express directly to your plant.
- Pre-Shipment Verification: High-definition photos, video testing runs, and serial number verification provided prior to shipment.
- Peace of Mind: Covered by our 12-Month Replacement Warranty.
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