Reflux Valves

Reflux Valves

O.M.I energy efficient frictionless footvalves and reflux valves (check valves) are products designed and manufactured by our R&D Team as per IS:10805. These are basically swing type non-return valves. Footvalves are available in screwed and flange type construction. Reflux valves have threaded portions at both the ends. They are specially designed to give an unrestricted smooth flow of water and thus to reduce the frictional losses to a minimum. Frictional losses in a valve can be defined by hf - KV² / 2g where, hf is friction loses in a valve, 'V' is the velocity of flow in the suction pipe and 'K' is the friction factor. The R.O.M.I frictionless footvalve has 'K' valve less than 0.8 and 'K' value for reflux valves are less than 0.5. Thereby it reduces additional load on prime mover and also gives more discharge.

All centrifugal end suction pumps will deliver water only when the entire pump casing and suction pipe is filled with water and without any air pockets (Priming). To achieve this, footvalve is necessary. Footvalve is placed at the lower end of the suction pipe of a centrifugal end suction pump to retain water in the pump casing and suction pipe while pump is at reset. Consequently when the pump is again started it does not have to be primed again and pump will deliver water instantaneously. It has a strainer at bottom portion; hence it prevents any foreign particles entering the pump through the suction pipe. The pressure withstanding capacity of footvalve is 1 bar. Reflux and non-return valves are fitted generally in the delivery pipeline to avoid water hammer, upthrust and backspin effects in the pumping system. These can also be used anywhere in the suction line of which the bottom end is entered into a bore pipe or tubewell. The pressure withstanding capacity of reflux valve and non-return valve are 1 bar and 15 bar respectively.

Salient Features

• Suction flow is almost straight hence frictional loss is minimal.
• It increases water discharge upto 20% and reduces power consumption upto 10%.
• Synthetic rubber flap totally prevents water leakage in the footvalve / reflux valves.
• Compact and easy to install.
• Specially designed ring washer prevents breakages.
• Easily replaceable parts.
  

Body

Body is made of graded cast iron. Flange type footvalve's flange holes are as per BIS standard IS: 10805. Screw type and flange type footvalves, checkvalves threading are as per IS: 554. Foot valves have a cast iron strainer with cored slots and adequate straining area.

Flap
The sealing is effected by means of a good quality rubber flap fitted with cast iron semi circular disc plates with appropriate weight to give perfect sealing of water.

Paint
Each valve has a coating of black paint conforming to IS: 158. This coating does not impart any taste or smell to water and it avoids rust formation.

Applications
Used in all pipe lines to reduce friction losses and improve discharge and reduce power consumption.