Gas valves are mainly used in:
In the gas burner
In the gas valve group connected to the gas blast burner
The gas valve is used as:
Stop valve (SKP1 connection)
Control valve with shut-off function
Regardless of whether the industrial combustion device has a waste heat recovery system or not, it can be used as a shut-off valve or controller in the air supply pipeline of this combustion device.
SIEMENS VVG 41.40 is a two-way threaded control valve primarily used in HVAC systems as a control valve or safety shut-off valve. Below is a detailed introduction to this valve:
I. Product Overview
Model: VVG 41.40
Type: Two-way threaded control valve
Connection: External thread connection, complying with ISO 228-1 standard
Rated Pressure: PN 16
Valve Body Material: Bronze (CuSn5Zn5Pb2)
Valve Stem, Valve Plug, and Valve Seat Material: Stainless steel
Nominal Diameter (DN): 40 millimeters
Rated Flow (kvs): 25 cubic meters per hour (when the valve is fully open, with a pressure differential of 100 kPa across the valve, and water at 5°C to 30°C flowing through the valve per hour)
Turndown Ratio (Sv): Determined by kvs and kvr, where kvr is the minimum flow rate that can still maintain regulating characteristics at a pressure differential of 100 kPa
Rated Travel: 20 millimeters
Leakage Rate: 0~0.02% of kvs value
Medium Temperature Range: -25°C to +130°C (suitable for cooling water, chilled water, low-temperature hot water, high-temperature hot water, saturated steam, etc.)
Application Fields: Suitable for heating systems, domestic water systems, open or closed systems in HVAC systems
II. Product Features
High Reliability: The use of stainless steel for the valve stem, valve plug, and valve seat ensures corrosion resistance and wear resistance, improving the valve's service life.
Precise Control: By adjusting the valve's opening, the flow and pressure of the medium can be precisely controlled to meet the system's different needs for medium flow and pressure.
Easy Installation and Maintenance: The external thread connection makes the valve easier and quicker to install, and the valve's design facilitates maintenance and inspection.
Wide Range of Applications: Suitable for various media and temperature ranges, meeting the needs of different systems and occasions.
III. Accessories and Attachments
Thread Accessories (ALG 2): Includes two nuts, two fittings, and two flat washers for valve connection and fixation.
Electronic Valve Stem Heating Element (ASZ6.5): When the medium temperature is below 0°C, this heating element should be used to prevent the valve stem from freezing.
Actuator: Can be installed in conjunction with SQX, SKD, SKB, and other series actuators for automatic control and remote operation of the valve.
IV. Installation and Usage Precautions
Installation Position: Generally installed on the return pipe, as the temperature of the return pipe in the heating system is lower, which can extend the life of the valve stem seal material.
Prevention of Cavitation: In chilled water circuits, it is necessary to ensure sufficient back pressure at the valve outlet to avoid cavitation. For example, a throttling valve can be installed after the heat exchanger to reduce the maximum pressure drop across the valve.
Medium Temperature Control: When the medium temperature is below 0°C, the electronic valve stem heating element should be used to prevent the valve stem from freezing. At the same time, for media containing antifreeze, the concentration of the antifreeze should be ensured to meet the requirements.
Regular Maintenance: Regularly check the valve's sealing performance and the tightness of the connection parts, and handle any abnormalities promptly.
V. Conclusion
The SIEMENS VVG 41.40 two-way threaded control valve is a high-performance, high-reliability control valve widely used in HVAC systems. Its precise control capabilities, ease of installation and maintenance, and wide range of applications make it an ideal choice for HVAC systems. When using it, attention should be paid to the installation position, prevention of cavitation, medium temperature control, and regular maintenance to ensure the normal operation of the valve and extend its service life.
