Boiler control valves are devices that regulate the flow of water, steam, or fuel to and from the boiler. They are essential for maintaining the proper operation and efficiency of the boiler system. Boiler control valves can be classified into two main types: isolation valves and modulating valves.
Isolation Valves
Isolation valves are used to shut off or open the flow of water, steam, or fuel completely. They are typically operated manually or automatically by an on-off switch. Isolation valves are often used for safety purposes, such as preventing leaks, overpressure, or explosions. They are also used for maintenance or repair work, such as draining or filling the boiler. Some common examples of isolation valves are ball valves, gate valves, and butterfly valves.
Modulating Valves
Modulating valves are used to adjust the flow of water, steam, or fuel partially. They are typically operated by an electric or pneumatic actuator that receives a signal from a controller. Modulating valves are often used for control purposes, such as maintaining the desired temperature, pressure, or level in the boiler. They are also used for optimizing the performance and efficiency of the boiler system. Some common examples of modulating valves are globe valves, needle valves, and sliding gate valves.
The table below summarizes the main differences between isolation valves and modulating valves.
| Isolation Valves | Modulating Valves |
|---|---|
| Shut off or open the flow completely | Adjust the flow partially |
| Operated manually or automatically by an on-off switch | Operated by an electric or pneumatic actuator that receives a signal from a controller |
| Used for safety or maintenance purposes | Used for control or optimization purposes |
| Examples: ball valves, gate valves, butterfly valves | Examples: globe valves, needle valves, sliding gate valves |
