NAB Swing Check Valve – API 594 for Seawater
Nickel Aluminium Bronze (NAB) swing check valves (NRV) manufactured to API 594 standard for seawater backflow prevention. Body and disc in ASTM B148 C95800. Class 150. Sizes 3" to 24". Ideal for pump discharge, seawater cooling systems, and marine applications.
Quick Summary
NAB Swing Check Valve = Non-return valve (NRV) made from Nickel Aluminium Bronze (ASTM B148 C95800). Allows flow in one direction, automatically closes on reverse flow. API 594 design. Used for backflow prevention in seawater systems. Available 3" to 24". No operator needed - automatic operation. Applications: pump discharge protection, seawater cooling, desalination, marine ballast.
Key Specifications
How Swing Check Valve Works
Forward Flow
Fluid pressure pushes disc open, allowing flow through the valve. Disc swings on hinge pin.
Reverse Flow
When flow reverses, disc swings closed and seals against seat, preventing backflow.
Automatic
No external operator needed. Valve operates automatically based on flow direction.
Frequently Asked Questions
What is a swing check valve?
A swing check valve (NRV) is an automatic valve that allows flow in one direction only. It has a hinged disc that swings open with forward flow and closes automatically when flow reverses. Used for backflow prevention and pump protection.
Why use NAB swing check valves for seawater?
NAB provides excellent corrosion resistance to seawater, anti-biofouling properties, superior erosion resistance, and self-healing oxide layer. Long service life without maintenance in marine environments.
What sizes are available?
NAB swing check valves per API 594 are available from 3" (DN80) to 24" (DN600). Common sizes: 3" and 6". Flanged, wafer, and lug styles. Class 150 pressure rating.
Need NAB Check Valves for Backflow Prevention?
We supply to major EPC contractors. EN 10204 3.1 MTCs. Third-party inspection available.
Related Products
Pricing – Swing Check Valve (Class 150)
indicative unit values (from factory India). Includes hydrostatic testing and EN 10204 3.1 MTCs. Volume discounts available for project quantities.
* Prices are indicative and subject to change. Contact us for confirmed pricing and delivery plans. GST extra as applicable.