Air cylinder

Figure 7-44.—Air cylinder. cylindrical or spherical in shape. Both types of cylinders are made up of two main parts—the container itself and a manifold assembly. The container serves as a trap for moisture, as well as an air storage space. The manifold assembly is made up of the “in” and “outlet” ports and a moisture drain fitting. See figure 7-44. Cooling of the high-pressure air in the storage cylinders will cause some condensation to collect in them. To ensure positive operation of systems, storage cylinders must be purged of moisture periodically. This is accomplished by slightly cracking the moisture drain fitting, located on the cylinder manifold. Some aircraft have a pneumatic system that will maintain the required pressure in these bottles in flight. However, most of these pneumatic systems require servicing on the ground with an external source of high-pressure air or nitrogen prior to each flight. Air storage bottles are serviced in the same manner as accumulators. Most air bottles have an air filler valve and a pressure gauge. These systems generally require higher servicing pressure than accumulators. Since gases expand with heat and contract when cooled, air storage bottles are usually filled to a given pressure at ambient temperature. A graph similar to that shown in figure 7-45 is usually mounted on a Figure 7-45.—Pneumatic storage cylinder inflation chart. 7-45