ZWT Type Self-operated Temperature Regulator

Product Overview

The ZWT series self-operated temperature regulator is widely used in pipeline systems for steam, hot water, oil, gas, etc. It requires no external energy source and automatically regulates and controls the medium temperature within the set range. It can also be used to prevent overheating or for heat exchange applications.

Main Technical Parameters

Applicable Media: Steam, water, oil, gas, etc.

Working Pressure: ≤1.6 MPa

Temperature Regulation Range: 20~40°C, 30~50°C,

40~60°C, ... 180~200°C

Regulation Accuracy: ±2°C

Service Life: 10⁵ h

Capillary Length: ≤10 m

Product Structure and Working Principle

The ZWT series self-operated temperature regulator (see schematic diagram) mainly consists of the main valve, diaphragm, auxiliary valve, bellows, temperature bulb, etc.

Working principle of downstream regulator: Before operation, the main valve is closed, and the auxiliary valve core is open under spring force. Hot medium entering from the inlet passes through the auxiliary valve into chamber F. When the flow through control valve D exceeds that through the small orifice, pressure in chamber F increases and flows through orifice E to the main diaphragm chamber A via external tubing, pushing the diaphragm upward to open the main valve core, thus opening the main valve. Medium flows through the main valve to the downstream section C, where the temperature bulb contacts the medium. When the medium temperature rises to the preset value, the liquid in the temperature bulb expands, pushing the bellows downward. The auxiliary valve stem follows to close the auxiliary valve port, reducing pressure in chamber F and subsequently in chamber A. The main valve core moves down to reduce the main valve opening, decreasing medium flow. As the controlled temperature fluctuates, this process repeats to regulate medium flow and achieve temperature control. When heating is not required, the main valve closes.

The working principle of the upstream regulator is opposite to that of the downstream regulator. When temperature increases, the main valve opens to stabilize the upstream temperature.

Specification and Model Parameter Comparison