Landing Valves & Hydrant Valves are one of the core components in a comprehensive fire-fighting system. Both Landing Valves & Hydrant Valves have a similar body design that is robust in its built and that is strong enough to withstand harsh environments. Although with very similar and inter-wined functions, both landing valves & hydrant valves have specific applications of their own. The name ‘Landing valves’ were used to describe valves for fire fighting provided on Risers in buildings, as these were typically located in staircase landings to allow easy access to Fire fighters. Hence, the name ‘Landing valve’ came to be associated with these types of valves in buildings. As firewater systems for municipal/ industrial applications are typically called hydrant systems, the term ‘Hydrant valves’ was used to describe the valves fitted on the Hydrant stand posts in such systems. Both terms actually refer to the same type of valve, though the term ‘Landing valve’ is more associated with building applications.
Landing Valve ideally should be installed in all the floors of a building whereas hydrant valve is installed in the ground floor. In case of fire, the firemen connect their hose to the landing valve that supplies water to extinguish the fire. Landing valves are permanently charged with water using a pressurized supply. The normal pressure of a landing valve is around 65 psi. When using a landing valve the operator must take extreme caution as opening or closing a fire hydrant too quickly can cause a water hammer which can damage nearby pipes and equipment. According to “Indian Standard Code Of Practice For Installation And Maintenance Of Internal Fire Hydrants And Hose Reels On Premises” (source: http://firesafeworld.com/indian-standard/), Landing valves should be installed on each floor level and on the roof, if accessible, in such a way that control line of landing valve is 1 to 1’2 m above the floor level.
Though the basic function of hydrant valves remains the same, depending upon application/ location/ code requirements, different designs and sizes are available. Normally, fire fighting equipment to be connected to and operated from a hydrant valve is designed for 100 psi (approx 7 kg/cm2) pressure. Hence the normal operating pressure is approx 7 kg/cm2. However, this may vary for different applications. For e.g. on large industrial complexes; the operating pressure may be in the range of 10-11 kg/cm2. Similarly, if small diameter hoses the pressure may be 4 to 5 kg/cm2.
Most standards around the world, including BIS, allow the use of different materials for construction for hydrant valves, which include Bronze, Aluminium, and Stainless Steel. The main requirements are mechanical strength, corrosion resistance and suitability to application.
AAAG India offers specially designed Hydrant and Landing Valves like Oblique, Downward, Horizontal & Right Angle.