VGZW230Self-operated Temperature Control Valve

Product Overview

The VGZW230 self-operated temperature control valve automatically adjusts the valve opening based on changes in the temperature of the controlled medium. It performs automatic temperature regulation without requiring an external energy source and is suitable for various heat exchange applications using steam, hot water, thermal oil, and other media. It is widely used in heating and air conditioning, domestic hot water, petrochemicals, power generation, electromechanical, textile, rubber, food, and other industries.

Structural Features

1.Utilizes the principle of thermal expansion of liquids and their incompressibility to achieve automatic regulation.

2.Liquid expansion within the sensor is uniform.

3.Control action is proportional regulation.

4.Passive operation (functions normally without electricity or compressed air).

5.The valve seal employs a V-ring high-temperature sealing assembly to prevent the valve stem from seizing due to overtightening or leaking.

Working Principle

The self-operated temperature control valve operates on the principle of thermal expansion and incompressibility of liquids. The liquid inside the temperature sensor expands uniformly, and the control action is proportional. When the temperature of the controlled medium changes, the volume of the temperature-sensitive liquid inside the sensor expands or contracts accordingly. If the temperature exceeds the set value, the temperature-sensitive liquid expands, pushing the valve plug downward to close the valve and reduce the flow of heating medium. If the temperature is below the set value, the temperature-sensitive liquid contracts, and the return spring pushes the valve plug open to increase the flow of heating medium.

Main Parameters and Performance Indicators
Nominal Diameter (mm) 15 20 25 32 40 50 65 80 100 125 150 200 250
Flow Capacity C Value 3.2 5 8 12.5 20 32 50 80 120 180 260 350 450
Nominal Pressure (MPa) PN16 (1.6MPa, valve body material: cast iron), PN25 (2.5MPa, valve body material: cast steel)
Temperature Setting Range (°C) 35°C~110°C
Capillary Length (m) Standard length 3.5m; custom lengths 5m, 10m, 15m
Maximum Operating Temperature Cast Iron 180°C
Cast Steel 350°C

Main Component Materials
Valve Body ZG230-450, ZG0Cr18Ni12Mo2Ti, ZG1Cr18Ni9Ti
Valve Seat 1Cr18Ni9Ti, Cr18Ni12Mo2Ti
Valve Plug 1Cr18Ni9Ti, Cr18Ni12Mo2Ti
Bellows Housing 1Cr18Ni9Ti, Cr18Ni12Mo2Ti
Balancing Bellows 1Cr18Ni9Ti
Temperature Bulb H62, 1Cr18Ni9Ti
Capillary Tube H62, 1Cr18Ni9Ti
Connector 35, 1Cr18Ni9Ti


Main External Connection Dimensions
Nominal Diameter (mm) L H1 D D1 D2 d G H2 n-Φd Weight (kg)
32 180 555 135 100 32 25 1-1/4 180 4-Φ18 23
40 200 570 145 110 40 25 1-1/4 180 4-Φ18 25
50 230 610 160 125 50 25 1-1/4 280 4-Φ18 28
65 290 635 180 145 65 25 1-1/4 280 4-Φ18 33
80 310 680 195 160 80 25 1-1/4 280 8-Φ18 45
100 350 720 215 180 100 25 1-1/4 280 8-Φ18 57
125 395 760 245 210 125 25 1-1/4 380 8-Φ18 73
150 470 800 280 240 150 25 1-1/4 380 8-Φ22 100
200 550 950 335 300 200 25 1-1/4 480 12-Φ22 200
250 640 985 405 355 250 25 1-1/4 480 12-Φ22 250