Liquid Level-2 Regulator Valve

Liquid Level-2 Regulator Valve
UFSB-2W-C type

Maintains liquid level between upper and lower limits

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With over-discharge cutoff function

By level-2 control, the supply of water is replenished after the stored water has been used up, assuring a constant supply of fresh water.

Equipped with a flow rate regulating function that cuts the over-discharge and maintains the set flow rate.

The unique closure mechanism realizes complete water shutoff performance and leakage prevention when fully closed.

The pilot valve does not have any minute, fixed restriction passage like a needle valve, and is therefore clog-resistant.
And, even if clogging by foreign material occurs, the built-in self-cleaning mechanism causes the clogged valve part to open automatically to remove the foreign material.

Due to its simple construction, troublesome adjustments are unnecessary. Being excellent in durability and practically maintenance-free, using this valve reduces maintenance costs.

Liquid Level-2 Regulator Valve

Patented in Japan, U.S.A., other



Rated pressure



A ball tap with an upper limit ball and a lower limit ball is connected by piping to the pilot valve, and the pilot valve is driven by the opening and closing of the ball tap at the set water levels (HWL and LWL) to automatically adjust the main valve opening and control the water supply at two levels, i.e. shutoff at HWL and starting of supply at LWL.
Also, an orifice is provided at the inlet side of the valve, and over-discharge is prevented by operation of the pilot valve driven by differential pressure (P1-P1') that arises between the front and the rear of the orifice due to the flow rate fluctuation.


Even when the water level drops from HWL, the ball tap remains closed due to the toggling mechanism and the main valve is kept in the fully closed condition.
Next, when the water level drops to LWL and the weight of the lower limit ball begins to act, the toggling mechanism is released, causing the ball tap to open and the pressure on the top of the main valve to be released, thereby causing the main valve to become fully open and the water supply to start. The water supply is then continued until the water level reaches HWL and the buoyancy of the upper limit ball reverses the toggling mechanism.


The arrangement for over-discharge prevention is the same as that of the UFSB-1W-C type. If flow rate control over a wide range is required, a butterfly valve or other flow rate adjustment valve (optional) may be installed in place of the fixed orifice.


Inlet pressure (Primary pressure)
Max. 1MPa (For JIS 10K standard)

Operating differential pressure
0.1MPa or more

Level difference between HWL and LWL
Can be set freely

Liquid Level-2 Regulator Valve /  Flow rate characteristics

Selection chart/Outer dimensions

Please refer to Common specifications & Outer dimensions.

Technical data
Selection & Dimensions
Inquiry form

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