▶ Special Feature 

● The best for controlling high water level in medium capacity water tank.
● The valve has excellent service life due to the valve worked by pressure     difference and piston style.
● Opening and closing height of valve is big and it is completely opening
    and closing style.
● There is control shaft assembled to control the flow rate of overflow by
    user.
● Easy to install as unifying the body and the pilot.
● Good to use where much flow rate is needed in short time.
● It is automatic level control valve that doesn't need any power source,
    however, can control fixed high and low water level.  

   BALEM 421 (Combi Valve) is a buoyancy type of water level control valve which is pilot integrated as one body for supply and controls water levels in a storage tank by utilizing the line static and differential pressure.
   BALEM 421 Valve has a full mechanical structure, so, it functions by itself without any external power source. It is easy to install due to inner control pipe and integrated pilot. Durability of the valve is excellent and shutting off is stable in high pressure since the valve functions by piston style opening/closing. This valve can get much flow rate of water quickly as it has pilot styled structure using the pressure difference.

▶ Specifications 

Model No.

421-080

80A(3")

0.05~0.98 MPa(0.5~10kgf/㎠)

1.72MPa(17.5kgf/㎠)

Temperature : 0°C ~ 80°C

End Connections

Screwed : KSPT(Standard) / NPT(Optional)

Weight

2.5kg

3kg

4.2kg

5.3kg

7kg

10kg

▶ Dimensions 

L2

W(ø)

▶ Materials 

▶ Flow Chart

▶ Standard Piping Diagram

▶ Principle of Operation

 ◆ OPEN
    When the water level in reservoir becomes low, the chamber connecting with pilot valve inside of body becomes in the condition of atmospheric pressure as opening pilot valve. At this time the power which subtracts the weight of piston assembly paying regard to buoyancy and the reaction force of spring from the power which multiply the difference of width(A-B) by the pressure of fluid supply lifts up piston and fluid can flow toward outlet.

 ◆ CLOSE
    When the water level in reservoir reaches to high water level just, pilot valve will automatically close. In this point, the chamber pressure inside of body is the same with the pressure of inlet by water route through the chamber and the liquid room of inlet, fluid flowing toward outlet will close since disc closes valve seat as moving downward by the weight of piston assembly and the power of spring. At this time, liquid pressure by the area of valve seat is total power of valve closing.

 ◆ Control Shaft
    Since flow rate out will be adjusted by the cycle height of piston moving, the cycle height of piston can control using control shaft same as the figure and can control flush out pressure and meeting spot condition.

▶ Applications

● As for Buildings. Apartments. Plants
    - For controlling the water level of water tank at underground/roof top water reservoir.
    - For controlling the water level of water tank at the elevated water tank.
    - Substitute for motorized  valve with electrode bar for controlling high & low water level.
    - For controlling the valve control of fuel oil tank.
    - For controlling the water level of cooling tower.

▶ Patents

- Korea Patents No. 0207682
- US Patent No. : 4830042
- Japan Utility Model No. : 2014053

▶ Installation

1. Refer to the standard piping diagram when installing the valve.
2. Install near a manhole, install a union for ease of maintenance, repair, and servicing.
3. Before installation, finish to clean pipeline.
4. A receiver alarm system needs to be installed in monitoring room for early detection of     malfunction.
5. To prevent waves while filling, an induction tube with syphon braking hole must be installed.
6. The water level sensor must be placed in the following order ;
    - low water level(pump start)
    - high water level(pump stop)
    - warning water level(alarm control fail)
    - emergency stop(closing pilot valve)