The Back Pressure Valve is a unique pressure controlling device intended to ensure continuous backpressure-constrained flow while in-operation of a fluid delivery system. While conventional relief valves are designed to protect downstream components from overpressure, this type of valve is used when it is required that the line pressure upstream varies with a predetermine… This restricts flow and helps in avoiding uncontrolled discharge thereby enabling correct operation of pumps (more specifically metering / dosing Pumps) within its performance bands.
Stability of the fluid column is crucial for industrial piping networks. Installation of a Back Pressure Valve during SWD system design mitigates siphoning risks, prevent low point discharges (when the discharge location is lower than storage tank) or under vacuum conditions. The valve stays closed until the upstream pressure overcomes a spring-held diaphragm relief before opening and relieves flow while holding system tension at all times.
Proudly molded using high-quality thermoplastic materials like UPVC, PPH and PVDF, these valves are a reliable solution in complex fluid circuits)application-gradegate(1)PostMapping.listFilesMatching(".*_USE-CASE_GATE.md").imgsUsedUnified. with their rigid, chemical-resistant trim packages till date! They are designed for the conveyance of aggressive media and contain no metal constituents, which means there is no danger from contamination or electrochemical corrosion; this makes them ideal to use in high-purity chemical dispense systems and corrosive slurry lines.
The structural integrity of the valve is derived from a combination of high-performance polymers and a precision-engineered internal mechanical assembly.
Most valves use a valve body made of Polyvinylidene Fluoride (PVDF) or Chlorinated Polyvinyl Chloride (CPVC ). These materials are highly resistant to concentrated acids, alkalis and organic solvents. This parameter sets chemical compatibility and mechanical strength of the valve over different heat applications respect to material choice.
It typically uses a PTFE-faced, bonded to EPDM-diaphragm for the backbone. They are also comprised of two materials, with a PTFE layer that contacts the fluid and an EPDM component to provide elasticity opening fatigue resistance for repetitive cycles. This design ensures hermetic seal and prevents fluid leakage into the spring chamber.
A high-strength stainless steel spring that is isolated from the process fluid applies force to keep the valve in a closed position. A spring is used in compression which can be adjusted using a screw mounted on top, allowing operators to adjust the opening pressure individually as required by their process.
The valve reduces the pulsations characteristic of positive displacement pumps by steadying them with a constant back pressure. The end result being an increased flow profile, and more accurate dosing of chemical which in turn reduces wear on downstream instrumentation / piping joints.
Technical configurations are designed to align with international industrial standards to ensure seamless integration into existing piping layouts.
The system is generally rated for a nominal pressure of PN10 (1.0 MPa). The adjustable range typically spans from 0.05 MPa to 0.7 MPa, providing flexibility for low-pressure chemical transfer and higher-pressure process applications. The precision of the set point is maintained even under fluctuating flow rates.
To accommodate various installation requirements, the valves are available with multiple end connections. These include socket fusion for PPH and PVDF systems, solvent cement sockets for UPVC and CPVC, and flanged connections for integration with metal or large-diameter plastic pipelines. Threaded options (NPT or G) are also available for secondary instrumentation lines.
The maximum operating temperature is strictly dependent on the body material. UPVC units are suitable for ambient service up to 60 °C, while PVDF variants can withstand more rigorous thermal conditions reaching up to 120 °C. Selection must account for the degradation of mechanical strength as temperatures increase.
The implementation of a high-quality Back Pressure Valve provides several operational benefits that enhance the longevity and safety of the entire fluid system.
In systems where the supply tank is elevated relative to the injection point, fluid can continue to flow even when the pump is deactivated. The valve acts as a reliable anti-siphon barrier, ensuring that flow only occurs when the pump is actively generating pressure above the set threshold.
The valve prevents the pump from "over-stroking" by ensuring it always works against a constant load, thereby keeping in primed at all times. The mechanical stability also lowers the strain on diaphragms and check valves in a pump head, leading to substantially longer mean time between maintenance (MTBM) intervals.
The top-entry design enables inspection and servicing of the diaphragm and spring without removing the valve body from a pipeline. This modularity reduces system downtime and allows for easily performed routine safety checks in critical chemical processes.
Non-Metal High-Density polymer materials are utilized keep the solenoid valve body impervious to aggressive environments such as salt-spray, or chemical storage areas. Its unique construction obviously does not require external coatings or regular rust treatment.
| Component | Material Specification | Technical Advantage |
|---|---|---|
| Valve Body | UPVC / CPVC / PPH / PVDF | Superior chemical inertness and rigidity |
| Diaphragm | PTFE / EPDM Composite | Dual-layer protection and high cycle life |
| Spring | Stainless Steel (Isolated) | Precise pressure tensioning and durability |
| Seals | FPM / EPDM | Reliable secondary containment and sealing |
| Connections | Socket / Flange / Thread | Versatile integration with global standards |
The Back Pressure Valve is a fundamental component in sectors requiring precise fluid control and protection against corrosive elements.
In municipal and industrial water treatment, these valves are used to manage the injection of chlorine, coagulants, and pH-adjusting chemicals. They ensure that the chemical is delivered at a constant rate, regardless of the fluctuating pressure in the main water line.
The high-purity requirements of the electronics industry necessitate the use of PVDF valves. The valve maintains the necessary pressure for ultrapure water (UPW) loops and acid etching systems while ensuring zero trace metal contamination.
In metallurgical facilities, the valves are used to control the flow of aggressive pickling acids. Their resistance to sulfuric and hydrochloric acid ensures long-term reliability in environments where metallic valves would fail rapidly.
The non-toxic and smooth internal surfaces of the thermoplastic valves prevent biological growth and facilitate clean-in-place (CIP) procedures, making them suitable for auxiliary fluid handling in pharmaceutical manufacturing.
Request a Quote
