What is the standard identification number for an AN union standard fitting?

• A. AN 805
• B. AN 815
• C. AN 825
• D. AN 835

Answer: (B)

The identification number for an AN union standard fitting is AN 815. AN fittings are part of an Army-Navy specification that ensures compatibility and reliability in fluid systems, especially in aerospace applications. Each fitting has a specific design and function that correlates with its identification number.

In this case, AN 815 specifically denotes a union fitting, which is designed to connect two different sections of a fluid line while allowing those lines to be disconnected for maintenance or replacement without the need for cutting or re-welding. The unique numbering system differentiates between various types of fittings and their applications, with AN 815 being recognized as the standard for unions, thereby providing a consistent reference within the industry.

Understanding this standard is critical for anyone working with fluid lines and fittings, as it ensures correct selection and application in assemblies where reliability and safety are paramount.