Safety Valves
The refrigerating system, no matter its size, is a closed system. This is a sealed container. Pressure vary, but high blood pressure can lead to some part of the system to explode. This can occur during stoppages, fires, extreme temperatures, or with faulty electrical controls.
To prevent any dangerous pressure relief valves are mounted on the unit. They, as a rule, liquid receiver, Hand valves should not be placed between the system and the safety valve. National Refrigeration Code and the majority of local programs require valves under the following conditions:
- If the unit is greater than a certain tonnage.
- If the number exceeds the specified refrigerant mini-moms.
- If the internal volume is sufficiently large.
Safety devices are of three basic types:
- Fusible plug,
- Rupture of the disk.
- Spring loaded valve.
She has a thread for connection to a liquid receiver. Flashed installation is used to connect the blowdown line is used for the transport of excepted refrigerant outdoors.
Low temperature alloy melts into the connector, the receiver if the temperature rises above a certain temperature. When the alloy melts, all the refrigerant will be released.
This model is used in large commercial chiller applications. Rupture of the disk is a thin metallic disk, which will burn up the pressure in the system reach a dangerous level. The device seals when the pressure is reduced. The system also contains a filter traps that collects the fragments of a broken disk.
Spring loaded safety valve seal itself or closed when the pressure drops to a safe limit. The relief of the pressure is regulated but, after the installation of the valve sealed to prevent tampering. This is shown in Fig. 13-152. It is important to reset not be adjusted held. The seal shall not be broken. If so, the valve must be replaced by a properly configured and closed the faucet. Pressure relief valves are typically 10-20% below their opening pressure of the...
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Industrial