Vortex Inhibitors

Applications

Vortex inhibitors are installed in every fire water storage tank where pump suction draws directly from the tank — underground tanks, elevated tanks, and industrial water reservoirs serving hydrant and sprinkler systems.

Gujarat warehouse and industrial projects in Gandhidham, Mundra, and Dahej typically use underground fire tanks with submersible or suction pump configurations where vortex formation at high flow rates is a documented risk during witnessed Fire NOC flow testing.

• Fire water storage tanks for hydrant and sprinkler systems in commercial and industrial buildings
• Underground and elevated fire tanks in warehouse and logistics facilities
• Large industrial water reservoirs in chemical and pharma plants
• Replacement upgrades on existing tanks where pump cavitation or flow shortfall is diagnosed

Technical Specifications

Vortex inhibitors consist of a flat or domed plate mounted horizontally above the suction inlet at a specified clearance distance. The plate diameter is typically 2 to 4 times the suction inlet diameter, depending on tank depth and maximum flow rate.

Materials include mild steel with epoxy coating for standard installations, and stainless steel (SS 304/316) for coastal Mundra installations or chemical plant environments where corrosion resistance is critical.

Installation height above the suction inlet is typically 150–300 mm depending on design flow rate and tank depth. Incorrect height reduces effectiveness — too close restricts flow area, too far allows vortex formation below the plate.

Sizing and Selection Guidance

Vortex inhibitor diameter relates to tank size, maximum suction flow rate, inlet pipe diameter, and water depth above the inlet at minimum tank level. NBC and NFPA 22 reference anti-vortex provisions for fire tanks — most engineered designs include them as standard.

During tank design, specify vortex inhibitor requirements alongside suction inlet location and pump capacity. For retrofit installations where existing tanks show pump cavitation or fail to achieve design flow during testing, we assess whether a vortex inhibitor addition will resolve the performance shortfall before recommending pump upsizing.

Coordinate vortex inhibitor installation with tank construction — the plate mounts to support brackets welded to the tank wall or floor during tank fabrication. Retrofit into existing tanks requires draining and internal access.

Supply and Support

Rachna Fire & Safety includes vortex inhibitors in fire tank specifications for EPC projects and supplies standalone units for tank fabricators and civil contractors. We provide sizing recommendations based on pump hydraulic calculations and tank drawings.

Include vortex inhibitors in your fire tank BOQ — they are inexpensive components that prevent pump performance failures during critical Fire NOC witnessed testing.