Terminal Objective: Upon completion of this chapter, you will be able to describe safety precautions and procedures for handling liquid or gaseous oxygen and its support equipment, describe liquid oxygen storage procedures, and recognize contamination control procedures.

Oxygen systems on naval aircraft require several types of support equipment to ensure their safe and satisfactory operation. AMEs are concerned with support equipment that is used for storage and servicing of oxygen. In this chapter, storage tanks and servicing equipment are discussed. As an AME it is your responsibility to know and understand the safety precautions that are involved when working with or handling liquid or gaseous oxygen and its support equipment. This information should not stop with just the personnel of your rate, but it should be stressed to all aviation maintenance personnel, so they won't mishandle or mistreat AME support equip-ment. Examples include playing with valves of service trailers, standing or sitting on trailers, hauling tools and equipment on them, spilling oils and other fluids on them, etc. Their awareness will reduce the possibility of creating hazardous conditions that could cause serious injury to themselves or others. Safety precautions applicable to this chapter are covered throughout the text. Oxygen safety precautions can also be found in NAVAIR 06-30-501, Technical Manual of Oxygen/ Nitrogen Cryogenic Systems.

LIQUID OXYGEN STORAGE

Learning Objective: Describe safety precautions and handling procedures for liquid oxygen storage tanks, transfer lines, and valves.

Liquid oxygen (LOX) is centrally stored on naval air stations for issue to users. Few Navy requirements involve containers over 2,000 gallons. The design features and practices described in this chapter apply generally to all sizes of containers. The main emphasis is on tanks of 2,000 gallons and under. Figure 5-1 shows a 2,000-gallon-capacity storage tank.

TANKS

The tank is used for the storage of LOX at low pressure, with low evaporation loss, and for transferring of LOX to smaller containers, as required. All LOX storage tanks are basically similar, regardless of their size or configuration, whether they are skid mounted, trailer mounted, or permanently installed. They all consist of an

Figure 5-1.- 2,000-gallon-capacity liquid oxygen storage tank.

inner and outer container separated by a circular insulated space (the annulus) that is packed with a powder-type insulating material and highly vacuum pressured to minimize heat transfer and evaporation losses.