Non-Return Valves

Our PPH non-return valves deliver dependable one-way flow control across a wide range of chemical, industrial and corrosive liquid applications. Made from polypropylene homopolymer (PP-H) in a distinctive beige-grey finish, this specialised valve series combines chemical resistance, abrasion resistance and robust performance - ideal for demanding hot corrosive liquids and aggressive media found in chemical processing and industrial systems.

Polypropylene offers excellent durability in harsh environments, resisting acids, alkalis, solvents and many other chemicals without degrading, while maintaining structural integrity and pressure performance.

The simplest and most direct solution for basic one-way flow control, plain (metric) non-return valves are designed with smooth ends for solvent fusion welding into polypropylene systems. These valves allow fluid to flow freely in one direction and automatically close to prevent reverse flow when pressure drops or direction changes, making them ideal for general chemical and process plumbing.

Available with either EPDM seals for standard chemical resistance and broad compatibility, or FPM (Viton) seals for enhanced performance in higher temperature and more aggressive chemical environments, these valves are perfect for compact systems where welded connections are preferred.

Key features:

• Simple, lightweight construction
• Fusion ends for seamless PP-H pipeline integration
• EPDM or FPM seal choices for flexibility
• Wide suitability across chemical and process fluids

For applications where welding isn’t practical - such as retrofit projects or mixed-material systems - our BSP threaded non-return valves offer a versatile alternative. These valves are fitted with BSP threads for easy screw-in installation into threaded pipework, branch tees or adaptors.

With options featuring FPM seals, these threaded non-return valves provide reliable chemical resistance and good sealing performance in systems where disassembly or future maintenance may be required.

Key advantages:

• Quick, tool-friendly installation
• Suitable where fusion isn’t preferred
• FPM seal option for high chemical resistance

Wafer check valves are compact, lightweight non-return valves engineered to fit snugly between flanges without requiring long face-to-face dimensions. Their slimline, flangeless design minimises installed length and weight, making them ideal for systems where space is limited or where pipework needs to stay as compact as possible.

Constructed from polypropylene with your choice of EPDM or FPM seals, these wafer valves provide smooth, reliable closing action that prevents backflow without significantly increasing pressure drop. The wafer style also makes them easy to install between standard flanges, simplifying pipework layout and reducing fitting complexity.

Typical benefits:

• Space-saving wafer design
• Easy flange-to-flange installation
• Smooth internal bore reduces flow resistance
• Suitable for corrosive and process media

For systems where more rapid or reliable closure is required, our spring-assisted wafer check valves combine the compact wafer format with an internal spring mechanism that helps the valve disc close more swiftly and consistently. This reduces the risk of reverse flow and minimises pressure surges or water hammer - especially valuable in variable-flow systems or vertical pipelines.

Available with EPDM or FPM seal options, these valves are particularly effective in larger-diameter installations and higher-pressure systems (typically up to 10 bar), offering dependable backflow protection in challenging process environments.

Why choose spring-assisted options:

• Faster, more controlled valve closure
• Helps reduce water hammer and flow reversal
• Ideal for vertical or dynamic systems
• Maintains reliable sealing under fluctuating flow conditions

Non-return valves play a crucial role in protecting pumps, compressors, vessels and sensitive equipment by preventing backflow that can cause damage, contamination or process disruption. In chemical, industrial or effluent systems, reliable one-way flow control helps enhance safety, system efficiency and longevity.

With the Pipestock PPH range you benefit from:

• Exceptional chemical resistance - polypropylene resists aggressive fluids that would degrade many metal valves
• Versatile application options - choose from plain, threaded, wafer or spring-assisted styles to match system needs
• Seal flexibility - EPDM for broad duty or FPM for enhanced chemical and temperature tolerance

Whether you’re building a new corrosive process line, retrofitting existing systems, or upgrading critical infrastructure, our PPH non-return valves provide the performance and adaptability engineers demand.