According to ASTM standards, what is the recommended ferrule type?

The recommended ferrule type according to ASTM standards is the threaded plug type. This choice is often favored because threaded connections provide a secure and stable assembly, allowing for proper sealing and ensuring that the ferrule remains firmly attached to the pipe or apparatus. The threaded design allows for easy installation and removal, making maintenance or any necessary adjustments more convenient. This reliability and ease of use help meet the rigorous requirements set forth by ASTM standards in various applications.

In contrast, other ferrule types may not provide the same level of durability or convenience. For example, slip-on plug types might be easier to install but can be less secure, leading to potential leakage. Welded types may offer a strong connection but could require more complex procedures for installation and removal, which might not align with ASTM's goals of practicality and safety. Compression types can be effective in certain situations, but they may not provide the long-term reliability that threaded types do in many applications outlined by ASTM standards.