Product

Self operated differential pressure control valve

Brand：Pneumatic eccentric butterfly valve 型号：ZL47F-16

Overview of Self operated Differential Pressure Control Valve
Self operated differential pressure control valve is a type of valve that does not require external energy sources (such as electricity or gas) to drive and relies on the pressure changes of the medium itself to automatically adjust the pressure difference. It dynamically balances the pressure difference (Δ P) before and after the valve through a spring pressure sensing membrane valve stem linkage mechanism to ensure stable system operation. Its core function is to eliminate residual pressure head in the pipeline network, stabilize flow, and prevent water hammer effect. It is widely used in household metering heating, HVAC, and industrial fluid control systems.
working principle
Pressure balance mechanism:
The pressure conduit guides the outlet pressure (P ₂) into the upper sealing chamber of the pressure sensing membrane, forming a pressure difference (Δ P=P ₁ - P ₂) with the inlet pressure (P ₁).
When Δ P deviates from the set value (Δ Ps), the pressure sensing film drives the valve stem to move, adjusts the flow cross-section, and makes Δ P approach Δ Ps.
For example, when P ₁ increases and Δ P>Δ Ps, the valve opening decreases to increase resistance, causing P ₂ to rise and Δ P to fall.
Dynamic response:
Response time<1 second, adjustment accuracy ± 5%~± 10%, suitable for variable flow systems.
Technical Characteristics
Parameter Range/Description
Differential pressure adjustment range 0.02~0.4MPa (some models support 10~300kPa)
Temperature tolerance -20 ℃~150 ℃ (high temperature models up to 650 ℃)
Nominal pressure PN1.6MPa (some models PN16~PN64)
Flow range 0.1~650m3/h (adjustable ratio 25:1)
Application scenarios
Household metering heating system:
Eliminate the impact of user flow adjustment on other users and avoid overpressure noise of the temperature control valve (such as radiator temperature control valve pressure ≤ 25kPa).
HVAC system:
Stabilize the pressure difference between the inlet and outlet of fan coil units or heat exchangers to prevent equipment damage caused by excessive water flow rate.
Industrial fluid control:
Protect pumps and heat exchangers in chemical and petrochemical pipelines to extend equipment lifespan.