Brass Swing Check Valve Type RK104 — Threaded Check Valve with Female Thread
The brass swing check valve type RK104 is a threaded check valve with a pivoting disc. Both connection ends feature female-to-female thread. During forward flow the disc swings open. It thereby clears the flow path. On reverse flow it closes automatically. In this moment it seals reliably against the seat.
Unlike poppet-style check valves, the disc does not sit fully in the media stream. Pressure loss therefore stays at a minimum. The swing check valve with female thread is available in two variants. The RK104-MMNOI-NBR variant ranges from 3/8″ to 2″ and uses an NBR seal. The RK104-MMMOI-Metal variant ranges from 3/8″ to 4″ and uses a metallic seal.
The maximum operating pressure is 12 bar. The temperature range is –10 °C to +90 °C. Thread connections conform to ISO 228/1. FERGO supplies the brass non-return valve threaded in both seal variants ex stock.
Technical Data and Connection
The brass swing check valve is available in ten nominal sizes. They range from 3/8″ to 4″. The NBR variant covers sizes up to 2″. The metal-seal variant extends up to 4″. Pressure ratings include PN8, PN10 and PN12 — depending on nominal size. The operating temperature range extends from –10 °C to +90 °C. Both connection ends feature female thread to ISO 228/1.
Thanks to the pivoting disc design, pressure loss stays significantly lower than in poppet check valves. Moreover, even slightly contaminated media pass the brass check valve socket without increased resistance.
Materials and Sealing
Body and disc of the brass swing check valve are manufactured in brass. This proven material offers high corrosion resistance. It withstands water, heating media and slightly oily fluids. The RK104-MMNOI-NBR variant seals with an NBR gasket on the disc. It suits water, compressed air and heating systems.
The RK104-MMMOI-Metal variant uses a metallic seal. As a result, it extends the application range to higher temperatures. It also handles media where elastomers reach their limits. In addition, both variants offer a compact form factor. This makes them ideal for direct installation in threaded pipelines.
Applications and Ordering
The swing check valve PN12 protects drinking water lines reliably against backflow. The same applies to heating circuits, compressed air systems and industrial process lines. The low pressure loss is a key advantage. Added to this is the ability to handle slightly contaminated media. This combination makes the brass check valve threaded an economical alternative to ball and poppet check valves in compact piping installations. For custom solutions, project quantities or technical advice, the FERGO team is available.
