Product Overview

Function
The FLOWCAL automatic flow balancing valve guarantees a constant flow rate when the upstream/downstream pressure differential varies.
It is therefore necessary to refer to the ∆p vs. flow rate diagram and to a basic diagram illustrating the operation methods and the relevant
variable effects.
Operating principle
The FLOWCAL flow cartridge is composed of a cylinder, a spring-loaded piston, and a combination of fixed and variable geometric orifices
through which the fluid flows. These variable orifice sizes increase or decrease by the piston movement, contingent on the system’s fluid thrust. A
specially calibrated spring counteracts this movement to regulate the amount of fluid which may pass through the valve orifices, maintaining a
balanced system. FLOWCAL valves are high performance automatic flow balancing valves which control selected flow rates within a very tight
tolerance (approximately 10%) and offer a wide range of operation.
In this case, the spring-loaded
regulating piston remains in equilibrium
without compressing the spring and
gives the fluid the maximum free flow
area. When below the differential
pressure control range the piston acts
as a fixed orifice and thus the flow rate
through the FLOWCAL depends only
on the differential pressure.
If the differential pressure is within the
control range, the spring-loaded piston is
positioned to give the fluid a free flow
area permiting regular flow at the nominal
rate for which the FLOWCAL is set up.
In this case, the spring-loaded piston fully
compresses a spring and leaves only the
fixed orifice for the fluid to pass through.
The flow rate through the
FLOWCAL
depends only on the differential pressure.
2 psi 32 psiDIFFERENTIAL
P
RESSURE
FLOW RATE
G
0
Range ∆p 2–32 psi where G
0
= nominal flow rate
DIFFERENTIAL
PRESSURE
FLOW RATE
G
0
Control range
Initial ∆p
Final
∆p
2 psi 32 psi
Range ∆p 2–32 psi where G
0
= nominal flow rate
FLOW RATE
DIFFERENTIAL
PRESSURE
G
0
2 psi 32 psi
FLOWCAL
T
M
Automatic Flow Balancing Valves
Below the differential pressure control range (< 2 psid)*
Within the differential pressure control range (2 - 32 psid)*
Above the differential pressure control range (> 32 psid)*