Apparatus
(a) Apparatus. A vibration testing machine that supports a brake tubing assembly by its end fittings in approximately a straight line and includes the following features: (1) One tubing assembly attachment point is fixed and the other moves in a plane perpendicular to a line projected between the attachment points. The movable attachment point moves in a linear direction and travels 1/2 inch total and at its midpoint of travel falls on a line projected between the attachment points. The movable attachment point has a cycle rate of 600 cycles per minute. (2) The distance between the attachment points is adjustable to compensate for varying lengths of brake tubing assemblies. (3) The actuating mechanism for the movable attachment point is balanced to prevent introduction of machine vibration into the brake tubing assembly. (4) The machine has a compressed air supply system that pressurizes the air brake tubing assembly through one fitting while the other fitting is plugged. The machine's compressed air supply system includes a pressure gauge or monitoring system and an air flow meter. (5) The machine is constructed so that an air brake tubing assembly mounted on it can be conditioned in an environmental test chamber.