Sizes for rigid tubes were already standardized with sizes called out by tubing od 316 12 etc. A fitting listed at 3 dash three refers to the inside diameter of the fitting for instance a 3 an would fit a metal tube outside diameter of 316 inch.
An Thread Wikipedia
What is an an fitting. An stands for army navy. An army navy sizing was established many years ago by the us. An air force navy aeronautical standard and and air force navy aeronautical design standard are standards used by the us. Over the years we have received quite a few inquiries regarding an fittings. These fittings are made to meet strict performance standards related to the aeronautical industry. Of 216 or 18 while an an 8 fitting will fit a tube with an od.
The designation an stands for armynavy and calls out military specifications milspec for dimensional standards of hydraulic lines hose end connectors and port adapter fittings. An hose sizes were designed to match the id sizes of these rigid tubes. Armed forces a for army and n for navy describe the outside diameter od of tubing in 116 inch increments. They are similar to other 37 flared fittings such as jic which is their industrial variant. This standard of measurement is based on the nominal outside diameter od of the rigid metal tube that each size fitting is used with. The two are interchangeable in theory though this is typically not recommended due to the exacting specifications and demands of the aerospace industry.
Historical context of the an fitting an stands for air force navy aeronautical design standards also known as army navy that are used in us. An sizes originally developed for use by the us. The idea behind an hoses and an fittings was to provide a flexible alternative to rigid tubing in plumbing systems on aircraft and military vehicles. An fittings also known as armynavy were originally developed as a military standard that dates back as early as world war ii. An fittings are a flare fitting using 37 flared tubing to form a metal metal seal. An specifications are a popular standard met by all companies that manufacture an style performance fuel hose and accessories.
An fittings are manufactured to meet above standards. They were originally used in the aerospace industry. The size specifications were established by the military back in world war ii. Do not use an fittings with different flare type fittings. Military to set a common standard for designating hose size. Understanding port threads adapter fittings and line sizes.
For example an an 2 fitting will fit a tube with an od. Military in aviation applications. Of 816 or 12. An fittings use a 37 degree flare as the sealing surface.
Gallery of What Is An An Fitting
