Float-Type Regulator Valve

Float-Type Regulator Valve
UFSF type (PAT.)

Liquid level and constant flow rate regulation with compact float

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

Bore	80-600mm
Rated pressure	1MPa

>Selection & Dimensions

Definitive model of disk-float-type valve with compact float and tank

Multi-functional with liquid level regulation, constant flow regulation (UFSF-C type), and automatic shutoff of the flow when the liquid level reaches the upper limit.

For general use:	UFSF-S type (Standard type)
For constant flow regulation under any condition:	UFSF-C type (Full range constant flow regulation type)

	Compact float and compact tank
	The unique balancing mechanism enables secure liquid level control using a compact float regardless of the inlet pressure, and allows the float tank to be a significantly compact size. Also, due to this balancing mechanism, the valve operation is very smooth, causing no water hammer.
	Complete water shutoff possible
	Due to the balancing mechanism, an automatic self-closing force develops near the closing of the valve, which not only allows for use of a compact sized float, but also provides complete water shutoff performance.
	Durability and maintenance-free
	Due to its simple construction, the valve is clog-resistant, durable and practically maintenance-free.
	Full range constant flow regulation (UFSF-C type)
	Constant flow regulation is performed over the entire range even when the inlet pressure fluctuates. Excessive replenishment of water is therefore prevented even when the inlet pressure is high, enabling balancing of water supply among water distribution works, farm ponds, and other. Wasteful use of water resources can be prevented by setting the minimum necessary flow rate. The set flow rate can be changed when necessary with the maximum flow rate adjustment screw, enabling the water supply quantity to be changed according to season.
	Demonstrated performance
	Excellent performance as verified by the National Institute for Rural Engineering.

Structure & Principle (PAT.)

UFSF-C type (Full range constant flow regulation type)

1.	When the float begins to ascend as the liquid level in the float tank rises, the shaft is pushed down, narrowing passage A around the adjustment valve disk. This reduces the flow rate and intermediate pressure Pe begins to drop.
2.	Accordingly, the sliding valve is pushed down by inlet pressure P1 that acts on the top of the diaphragm, thereby narrowing passage B and causing intermediate pressure Pe to be restored to the original pressure. The differential pressure between the front and the rear of the adjustment valve disk is therefore maintained at a constant value and the valve can be opened and closed very easily regardless of the inlet pressure.
3.	As the liquid level continues to rise, the sliding valve is pushed down further, ultimately coming in contact with the shaft step and is integrated with the adjustment valve disk via the shaft, thus causing inlet pressure P1 acting on the bottom of the adjustment valve disk to become balanced with inlet pressure P1 acting on the top of the diaphragm.
4.	As a result, the axial thrust of the valve shaft balances, allowing the valve to be opened and closed very easily and realizing secure water shutoff with a compact float. (The length of the float arm may thus be made short, which reduces installation space and costs).
5.	When the liquid level drops, the valve acts sensitively in response to the movement of the float and begins to supply water. The adjustment valve disk becomes fully open when the liquid level drops further. Since the valve itself has a constant flow regulating mechanism, a stable flow rate is maintained even if the inlet pressure fluctuates.
6.	Water discharge is moderate and quiet due to the effective pressure reducing mechanism with the interaction of the adjustment valve disk and the sliding valve. The float tank can be made significantly compact in comparison to conventional valves, achieving a reduction of construction space and costs.

Flow rate characteristics
UFSF-C type (Full range constant flow regulation type)

	Constant flow rate characteristics at each set flow rate S (float valve opening %)

This UFSF-C type valve prevents over-discharge by adjustment of position S (stroke %) of the maximum flow rate adjustment screw, and a stable constant flow rate is maintained across the entire range regardless of the fluctuation of the inlet pressure. The constant flow regulation is securely maintained even at a low flow rate; thus allowing the minimum necessary flow and preventing wasteful use of water resources. UFSF-S type (Standard type) does not have the same constant flow regulation mechanism as the UFSF-C type, but it is equipped with the same shaft thrust balancing mechanism, enabling complete water shutoff with a compact float. This UFSF-S type also has a feature that allows maximum supply of water in accordance with the inlet pressure, and desired characteristics may be set by adjusting the position of the maximum flow rate adjustment screw.

Example of pipeline system

Example applications


	Sumoto Land Improvement Office in Hyogo Pref.		Takaoka Agricultural Land and Forestry Office in Toyama Pref.		Seibu Agriculture and Forestry Office in Shizuoka Pref.
UFSF-500		UFSF-300		UFNF-100


	Adopted in the 1997 New Technology Introduction Project by the Tohoku Agricultural Administration Bureau

As an alternative, depending on site conditions, Liquid Level Regulator Valve, employing ball taps, is also available.
For details, please refer to Pilot-Type Regulator Valves (Overview).

Selection chart & Outer dimensions

Specifications/Performance

Inlet pressure (Primary pressure):		Max. 1MPa (For JIS 10K standard)
Applicable liquid:		Various liquids at temperatures of 0-70 degree C (Please inquire for special liquids.)
Flow rate accuracy of UFSF-C type:		+/- 10%
Flange standard:		JIS 10K, JIS B2062 Waterworks standard
Material	(Valve case/Valve disk):	FC/SUS, FCD/SUS Besides the above, a wide variety of materials are available, such as YOKOTA's duplex type stainless steel YST130N with high corrosion resistance.
	(Float):	FRP
Cavitation characteristics:		The allowable cavitation coefficients (cc) are: With a bore less than 100mm: cc=0.45 With a bore more than 150mm: cc=0.24 For details, please refer to this page.

Selection chart

UFSF-S type (Standard type)

How to use the selection chart
Plot point C with x-axis value A and y-axis value B, where A is a planned differential pressure between the front and the rear of the valve, and B is a planned flow rate. Then select a valve with a bore size line immediately above point C. In the example on the left, a 250mm bore valve is selected.
Note:
	The selection chart is based on the maximum flow speed of 3m/sec. If a planned maximum flow speed exceeds this level, please contact us.
	The flow rate set by the maximum flow rate adjustment screw should be more than 10% of the maximum flow rate.

UFSF-C type (Full range constant flow regulation type)

Bore mm	Model No.	Maximum flow rate
		Standard pressure type		Low pressure type
		(m³/min)	(l/sec)	(m³/min)	(l/sec)
`80`	`UFSF-080C`	`0.36`	`6`	`0.24`	`4`
`100`	`-100C`	`0.66`	`11`	`0.36`	`6`
`150`	`-150C`	`1.50`	`25`	`0.90`	`15`
`200`	`-200C`	`2.64`	`44`	`1.50`	`25`
`250`	`-250C`	`3.90`	`65`	`2.28`	`38`
`300`	`-300C`	`6.00`	`100`	`3.60`	`60`
`350`	`-350C`	`6.60`	`110`	`3.96`	`66`
`400`	`-400C`	`8.70`	`145`	`5.10`	`85`
`450`	`-450C`	`12.90`	`215`	`7.50`	`125`
`500`	`-500C`	`13.80`	`230`	`8.10`	`135`
`600`	`-600C`	`19.20`	`320`	`11.40`	`190`

Note:
	The flow rate set by the maximum flow rate adjustment screw should be more than 10% of the maximum flow rate.
	The model No. for low pressure type valves is followed by "L". (e.g. UFSF-200CL)
	Operating differential pressure Standard type: 50-500kPa Low differential pressure type: 20-200kPa

Outer dimensions/Installation dimensions

Independent float tank type (The adjustment plug key and the float tank are optional accessories.)

Float-Type Regulator Valve / Independent float tank type

Submerged type	Integrated float tank type (Bore: 150mm or less)

	The dimensions indicated in the drawings are minimum dimensions which take into account required maintenance such as assembly and disassembly and refer only to cases where there is a farm pond adjacent to the valve chamber. If an independent valve chamber is added to a pipeline (i.e. there is no farm pond adjacent to the valve chamber), depending on flow conditions, there may be rapid fluctuations in water level in the float tank, causing water hammer at the front or the rear of the valve chamber. Therefore avoidance of such water hammer should be considered in deciding the size of the valve chamber. For deciding its size, it is recommended to refer to guidelines such as "Pipeline Design Manual" supervised by the Ministry of Agriculture, Forestry and Fisheries of Japan. If you need more help, please contact us.
	Since leg parts are not provided for valves with a bore of 150mm or less, please support those valves with the piping.
	If air is sucked into the outflow pipe of the valve chamber, a partition plate should be installed and the valve's discharge opening should be placed below the lowest water level.
	To mount the float tank, please affix it to the side wall of the chamber with a band, or, if placing it on the bottom of the chamber, provide a passage hole at the lower part of the float tank.
	Since the float can be attached on either the left or right side of the flow direction, please specify when making an inquiry.