Valves · Non-Return Technology
Check Valves & Non-Return Valves
Check valves and non-return valves prevent unwanted backflow of media, protecting pumps, compressors and system components from reverse flow and water hammer. STASTO offers both designs across a wide range – from axial and angle-seat versions to inline check valves. Select by nominal size, material or design type.
Axial, Angle-Seat & Flap – All in One Category
Why STASTO
Check Valve Selection by Technical Criteria
From axial-pattern to angle-seat to inline check valves – the right design for your installation situation and medium, all in one category.
Two Design Principles from One Source
Axial check valves, angle-seat check valves, and wafer check valves – the right design for your installation situation and medium, all in one category.
Wide, Structured Product Range
Multiple product series per design type allow selection by connection type, nominal size, and material – from standard check valves to wafer check valves.
Selection by Technical Criteria
Nominal size, cracking pressure, installation orientation, and material pairing take centre stage – we provide the technical fundamentals for a sound decision.
Configuration Advice
Not sure which series or material variant is right? Our technical sales team will support you in making your selection – get in touch with us.
Design Clusters
Check Valves by Design
Choose the right design for your installation situation and medium – axial, angle-seat and swing check valve types, as well as standard check valves and accessories.
Design Comparison
Axial, Angle Seat or Wafer?
The three design principles differ in seat arrangement, pressure drop, typical nominal size and installation. The following overview provides an initial orientation.
| Inline check valve | Lift check valve | Swing check valve | |
|---|---|---|---|
| Design principle | Spring-loaded cone/piston in axial direction | Seat arranged at an angle to the flow axis | Plate-type, inline-mounted (wafer) |
| Pressure drop | Moderate | Tends to be low | Depends on design |
| Typical nominal size | Smaller nominal sizes | Small to medium nominal sizes | Larger nominal sizes |
| Installation | Generally position-independent | Preferred mounting position depends on series | Sandwich plate, compact face-to-face length |
| STASTO series | 100000, 100001, 227, 228, 304/CH014-V, 316, VX23 | 1072, CH117, 4000 | CS-2466/CS-2424, CS-6666, CM-2466/CM-2424, CM-6666 |
Applications
Where check valves are used
Check valves and non-return valves are used wherever flow is permitted in one direction only. The appropriate design depends on the medium, nominal size and installation conditions.
Pump and compressor protection
Prevent backflow of media when shutting down and protect pumps and compressors against pressure surges and reverse flow.
Process and circulation lines
Backflow prevention in supply, circulation and process lines – check suitability and material depending on medium and series.
Gas and process media
Use depending on medium, pressure and material combination; refer to the respective series for permissible operating ranges.
Liquid circuits
Backflow protection in water and liquid circuits – select material and seal version according to medium.
Compressed air systems
Check functions secure flow direction in supply lines – select appropriate design depending on application.
Plant and equipment engineering
Compact check valves protect assemblies against backflow – select according to nominal size and installation conditions.
Guide
Choosing the right design
The choice between a check valve flap and a check valve – and within valves between axial and angle-seat designs – is guided primarily by four criteria.
Selection criteria
- Nominal size (DN) and connection
- Smaller nominal sizes are commonly covered by axial or angle-seat check valves; for larger pipelines, inline check valve flaps are often the more compact solution. Pay attention to the connection type (threaded, flanged, wafer) depending on the series.
- Pressure drop
- Angle-seat check valves tend to offer lower pressure drop due to their flow-optimised seat – relevant at high flow rates.
- Installation orientation
- Spring-loaded axial check valves can generally be installed in any orientation, while some designs have a preferred mounting position. The permissible installation orientation is specified for each series.
- Material and medium
- Body and seal materials must be compatible with the medium. Material variants (e.g. stainless steel, brass) are available depending on the series – the specific version can be found on the variant page.
Design types at a glance
- Axial check valve
- The closing element moves axially in the direction of flow; the spring-loaded cone or piston ensures fast, orientation-independent closure. Available in series 100000, 227, 228, 316 and VX23, among others.
- Angle-seat check valve
- The seat arranged at an angle to the flow axis provides a flow-optimised passage and lower pressure drop. Available in series 1072, CH117 and 4000.
- Check valve flap
- Disc-based, inline design, including wafer/sandwich flange type – compact and easy to install between flanges, ideal for larger nominal sizes.
Availability & Versions
Versions by Series and Variant
The range covers numerous series in various designs and materials. Availability, nominal sizes, permissible pressure and temperature ranges, and material variants differ depending on the series and variant – please refer to the relevant product or variant page for specific values, or contact our sales team.
Selection by Design, Nominal Size and Material
Browse directly within the series to find the design, nominal size and material that suits your application.
Material, Seal and Connection Variants
Body, seal and connection variants are available depending on the series – find the specific version on the variant page.
Lead Times and Stock Availability on Request
Information on lead times and stock availability is provided on request or on the respective product page.
Technical Enquiries and Special Versions
For special versions or technical enquiries, our sales team is happy to assist – please get in touch.
Frequently Asked Questions
Check valves & check flaps – FAQ
Answers to the most common questions about designs, selection and accessories.
What is the difference between a check flap and a check valve?
"Check valve" is the general term for fittings that prevent backflow; "check flap" (or check disc valve) typically refers to plate-based, inline designs (e.g. wafer type). Check valves include spring-loaded poppet and piston types such as axial and angle-seat designs. Both serve the same basic function but differ in construction, face-to-face length and typical nominal size.
What is an axial check valve?
In an axial check valve, the closing element moves in the direction of flow along the valve axis. Spring loading ensures rapid closure and typically allows installation in any orientation. STASTO carries series 100000, 227, 228, 316 and VX23 in this category, among others.
What are the characteristics of an angle-seat check valve?
The angled seat provides a flow-optimised passage, resulting in comparatively low pressure drop. Available from STASTO in series 1072, CH117 and 4000 – ideal for flow-critical applications.
Which nominal sizes and materials are available?
Nominal sizes, materials and seal versions vary depending on the series and variant. You will find the specific values on the respective product or variant page; please contact us for special versions.
How do I find the right design?
Base your selection on nominal size, required pressure drop, installation orientation and medium. Smaller nominal sizes are typically covered by axial or angle-seat check valves, while larger pipelines call for inline check flaps. If in doubt, our technical sales team will help you make the right choice.
Is matching accessories available?
Yes – in the same category STASTO carries suction strainers of series 110100 and ST304, which protect pumps and downstream fittings from solids.
Related Categories
Matching Valves & Accessories
Complement your check valve setup with further valves and fittings from the STASTO range.
Select now
Find the right check valve
Select your design by nominal size and material – or let our technical sales team assist you with the sizing.