SAE J844

Description / Abstract: This SAE Standard covers the minimum requirements for nonmetallic tubing as manufactured for use in air brake systems. Non-reinforced products are designated type A and reinforced products, type B. It is not intended to cover tubing for any portion of the system which operates below -40 °C, above +93 °C, above a maximum working gage pressure of 1.0 MPa, or in an area subject to attack by battery acid. This tubing is intended for use in the brake system for connections, which maintain a basically fixed relationship between components during vehicle operation. Coiled tube assemblies required for those installations where flexing occurs are covered by this document. SAE J1131, and SAE J2494-3 to the extent of setting minimum requirements on the essentially straight tube and tube fitting connections which are used in the construction of such assemblies².

General Requirements

Test temperature shall use ±3 °C as the test tolerance range.

All test times are minimum unless otherwise specified.

Dry air shall be a minimum of -50 °C dew point.

Tubing shall be cut square at 90 Degrees ± 7 degrees.

Precondition all test samples at 0.7 MPa ± 0.1 MPa for 30 s without leakage.

New sample shall be used for all tests.

1. See SAE J1149 for Metallic Air Brake System. Tubing and Pipe.

2. Federal regulations covering designed requirements and accepted applications for coiled tube assemblies are set forth in 49CFR393.45. Conformance to SAE J844 does not imply compliance with Federal regulations for air brake tubing. Sizes 3.97 mm and below may not meet 49CFR571.106 requirements for air brake systems.