Rexroth S Series Hydraulic Check Valve | S6 S10 S15 S20 S30 | One-way Valve

The S Series hydraulic check valves by Chengyuan Hydraulic are high-precision components fully compatible with Rexroth industrial standards. This range covers nominal sizes from S6 to S30, including popular models such as S6A1.2B, S10A1.2B, S15A1.2B, and S10A1/2. Designed to allow flow in a single direction while preventing backflow, these valves are characterized by precise cracking pressures, low pressure drops, and zero-leakage performance. We utilize high-strength steel with through-hardening treatment to ensure the valve poppet maintains extreme geometric precision even under high-frequency operation. All units offer 100% original-place interchangeability and undergo 100% pressure-seal testing to guarantee zero leakage in high-pressure environments.

Technical Specifications :

• Core Models: S6, S8, S10, S15, S20, S25, S30 (A series)

• Nominal Sizes (NG): 6, 8, 10, 15, 20, 25, 30

• Max Operating Pressure: $31.5\text{ MPa (315 bar / 4600 psi)}$

• Cracking Pressures: $0.05\text{ MPa (0.5 bar) / 0.15\text{ MPa (1.5 bar) / 0.3\text{ MPa (3 bar)}}$ (Defined by codes like 1.2/3)

• Max Flow Rate: Up to $450\text{ L/min}$ (For S30 size)

• Connection Type: Threaded connection (A series)

• Operating Medium: Mineral oil, Phosphate ester (Subject to seal material)

• Temperature Range: $-30\text{°C}$ to $+80\text{°C}$

Key Technical Advantages:

• Precision-Lapped Poppet & Seat: The contact surfaces between the poppet and the seat are micro-lapped to form a perfect conical seal. This ensures absolute zero leakage even when subjected to a full backpressure of $31.5\text{ MPa}$.

• Low-Resistance Flow Path: The internal geometry is optimized for fluid dynamics, maximizing the flow area and reducing turbulence. Compared to standard check valves, the S series reduces pressure drop by approximately $10\%$ at identical flow rates, lowering energy loss and system heat.

• Induction-Hardened Impact Resistance: The poppet is made of high-quality carbon steel and is induction-hardened ($HRC 58\text{–}62$). It can withstand hundreds of cycles per minute without plastic deformation, significantly extending service life in high-frequency switching systems.

• Stable Cracking Pressure Response: Integrated high-precision alloy springs ensure consistency in cracking pressure. Whether used for backpressure or standard check functions, the pressure fluctuation is kept within $\pm 5\%$, guaranteeing accurate system logic.

Application Areas:

• Industrial Power Units: Protecting pumps from reverse flow during shutdown.

• Accumulator Systems: Functioning as charging valves to maintain system pressure stability.

• Construction Machinery: Used as backflow preventers in stabilizer or pressure-holding circuits.

Expert Maintenance Tips:

• Orientation Check: Strictly follow the arrow marked on the valve body (flow direction) during installation. Reverse installation will completely block the circuit and may cause relief valves to trip.

• Cracking Pressure Selection: For return line backpressure, a $0.15\text{–}0.3\text{ MPa}$ spring is recommended. For simple backflow prevention, use the $0.05\text{ MPa}$ specification to minimize energy loss.

• Filtration Standards: Although check valves are robust, hard particles embedded in the seat will cause seal failure. Ensure system filtration is at least $25\mu\text{m}$ or better.