Precautions; Testing For Leaks - Piper PA-31-350 Maintenance Manual

PIPER AIRCRAFT
T-1020
MAINTENANCE MANUAL
PRECAUTIONS.
Before any maintenance is performed on the oxygen system, or any other system requiring removal of an
oxygen system component, personnel should read and understand these instructions. Careful adherence will
aid in maintaining a trouble free and safe system.
- WARNING -
Do not permit smoking or open flame near the airplane while
maintenance is being performed on the oxygen system. Ensure all
electrical power is disconnected and the airplane is properly
grounded. Keep all oils, grease, soap, and solvents awayfrom the
oxygen system. Hydrocarbons constitute a fire hazard and may
burn or explode when contacted by oxygen under pressure.
1. Use extreme caution to ensure all openings to the system are kept clean and free of water, oil, grease.
and solvent contamination.
2. Cap all openings immediately upon removal of any component. Do not use tape or caps which will
induce moisture.
3. Lubricants shall not be used anywhere in the system except those specifically approved for use with
oxygen systems. (Teflon tape and Krytox 240AC).
4. All oxygen system components must be handled with care to avoid damage.
5. Prior to working on the oxygen system, personnel must clean hands and tools. Cleanliness is
essential.
6. When removing regulator, retain all adjustment washers which fit around the adjustment shaft.
These washers are safety stops for maximum regulated pressure and must be used with reinstallation.
7. Avoid bending tubing or damaging flareless fittings.
8. All shut-off valves must be opened slowly. An explosion could result from rapid flowing oxygen
generating heat against metal.
9. Use only oxygen line leak detector fluid conforming to MIL-L-25567, Type 1. After leak test.
thoroughly wipe off all test solution to prevent corrosion/contamination.
10. Clean fittings and adjacent areas prior to opening system to prevent contamination when
disconnecting components.
11. Do not attempt to tighten fittings when system is pressurized.
12. Every two (2) years, oxygen system components (except tubing) should be removed, serviced,
cleaned /replaced.
13. Never allow electrical equipment to come in contact with the oxygen cylinder.
TESTING FOR LEAKS.
Apply leak detector fluid conforming to MIL-L-25567, Type 1. The solution should be shaken to obtain
suds or foam. The suds or foam should be applied sparingly to the joints of a closed system. Look for traces of
bubbles. No visible leakage should be found. Repair or replace any defective parts and retest system. With the
system pressurized to service pressure, further tests can be made. The rate of any leak should not exceed one
percent of the total supply per 24 hour period. All traces of the detector fluid should be wiped off at the
conclusion of the examination.
35-12-00
Page 35-04
Issued: September 2, 1981
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