Check valves

Return flaps - soft and metal sealing

Non-return valves are compact, high-performance components that reliably prevent the backflow of media in pipes thanks to their integrated flap, after which they are named. They are also often referred to as backflow flaps and have a similar function to non-return valves, but have a different design.

Functionality and applications of non-return flaps

These valves are used in numerous systems and pipelines, especially where liquid media flows, such as in wastewater disposal. The flap prevents backflow and is crucial to ensure proper operation of the system and to avoid potential contamination, especially in the wastewater area. When installed correctly, the non-return valve only allows the medium to flow in one direction.

The way these non-return flaps work is both simple and effective: the flap reacts to the pressure in the system. If the pressure rises above a certain value, the flap opens and allows the flow in the desired direction. If the pressure drops, the flap closes automatically and stops the flow. It also closes when the flow direction of the medium changes. This gives you control over the direction of flow and ensures that there is no backflow in the line.

In contrast to manually operated components such as butterfly valves or ball valves, the valve closes automatically as it interacts directly with the pressure in the pipeline, eliminating the need for manual intervention.

Flashback flaps at FILCOM - A wide range of models and variants

To ensure that a non-return valve fulfills its function optimally, it must be suitable for the respective system and the pipelines used. This is why you will find a wide range of models in the FILCOM range, including soft-seated and metal-seated versions. The butterfly valves can also be made of different materials such as brass or gunmetal.

We offer non-return valves with various thread sizes, including:

• G 1
• G 2
• G 1/2
• G 3/4
• G 1 1/2 and G 1 1/4

Please refer to the specific information on the respective product pages, especially regarding the temperature range and maximum line pressure. Non-return valves are designed for liquid media, but should not be used with steam. They are also not suitable for aggressive chemicals.

When selecting a product, pay attention not only to the thread but also to the DN and SW specifications, which are given in millimetres. Classic non-return valves can be used in a temperature range from 0 °C to a maximum of 90 °C.