Piercing-type valves should be used on which materials?

Piercing-type valves are designed for use with certain materials that require a puncture to access or introduce refrigerants. Specifically, copper and aluminum are commonly used in refrigeration systems where piercing-type valves would be appropriate. These materials are conducive to creating a seal when the valve is pierced, allowing for efficient refrigerant transfer without significant risk of leaks.

Copper is ubiquitous in refrigeration systems due to its excellent thermal conductivity and workability, making it ideal for piercing. Aluminum, similarly, is lightweight and strong, and can be effectively used with piercing-type valves in various applications.

In contrast, the other materials listed do not share the same attributes that make piercing-type valves suitable. Steel, while strong, often requires different handling and fittings due to its thickness and potential corrosion issues. PVC is a plastic material not compatible with puncturing methods, as it can crack or shatter when subjected to such stress. Lastly, brass, while it is often used in various fittings, does not typically require or allow for the effective use of piercing-type valves in the same manner as copper and aluminum.