TM 5-4220-233-14
b. Cleaning Hose Assemblies
(1)
Clean hose assemblies In accordance with the following steps using the specific materials and utilizing
proper equipment. Pre-clean hose assemblies outside the clean area by rinsing externally with
distilled water.
(2)
Most hose assemblies will not lend themselves to disassembly. Disassemble to maximum extent
without removing fittings or clamps
(3)
The cleaning solution shall be made by adding 1/2 ounce (14.7 mL) non-ionic detergent (Item 8,
Appendix D) to each 80 gallons (302.8 L) or distilled water.
(4)
Heat the cleaning solution to 120 degrees F (49 degrees C) and circulate through the hose assembly
for 30 minutes at a flow rate of not less than 1 gallon (3.8 L) per minute.
(5)
Rinse the hose assembly with distilled water heated to 125 degrees F (52 degrees C) for 30 minutes at
a flow rate of not less that 1 gallon (3.8 L) per minute. Do not recirculate the water.
(6)
Perform a shake test by collecting a 1000mL sample of rinse water in a flask (Item 9, Appendix D) that
can be fitted with a rubber stopper. Shake the flask for a few seconds and if any bubbles form and
remain on the surface of the water in the flask, continue to rinse the hose until no bubbles form and
remain in the sample flask.
(7)
Purge hose assembly with clean, dry, oil-free nitrogen (preferably heated to 200 degrees F (93 degrees
C)) until all visible signs of water are absent Continue drying process for 1 to 2 hours after initial purge.
NOTE
At no time shall the upstream purge pressure for all hose assemblies exceed 100 psig
(6895 millibars).
(8)
After drying, cover each hose end with a clean plastic bag (Item 2, Appendix D) to maintain internal
cleanliness. Secure the bag with 1 inch (2.5 cm) wide tape.
(9)
When components and systems have been assembled an air sample shall be taken to verify
cleanliness.
4-71. CLEANING METHOD - TRISODIUM PHOSPHATE (TSP ).
This method is the preferred method if all equipment is available. A steam/hot water cleaner that has
adjustable siphon control for cleaning applications works well.
a. For components the following steps should be followed:
WARNING
The TSP cleaning solution Is harmful to eyes and skin. Wear chemical protective apron,
gloves and goggles/face shield when handling or working with the solution.
(1)
Prepare a solution consisting of 2 pounds (0.9 kg) TSP (Item 17, Appendix D), 0.5 ounces (14 7 mL)
non-ionic detergent and 80 gallons (302.8 L) of distilled or deionized water.
(2)
Heat solution to 165 degrees F (74 degrees C) mixing occasionally during the heating.
(3)
Disassemble components down to the smallest parts (separate and clean soft goods and aluminum
parts as specified In paragraph 4-65) and soak in the solution for 10 minutes minimum, 30 minutes
maximum.
(4)
After soaking, clean the parts in the ultrasonic cleaner until all visible traces of contaminate dirt or
grease are gone.
(5)
For components too large for an ultrasonic cleaner, scrub the parts with a nylon bristle brush until all
visible traces of contaminate dirt or grease are gone.
(6)
Rinse all parts in running hot distilled water or deionized water until all visual traces of cleaning
solution are removed.
(7)
Draw 0 34 ounces (10 mL) sample Agitate or rinse water to observe for soap bubbles. if any soap
bubbles are present, repeat steps 6 and 7 until no bubbles are observed.
(8)
Blow dry components with clean air, nitrogen or helium.
(9)
Reassemble components using an approved lubricant.
(10) Bag and seal or tape closed all components and ends of pipe or hoses with plastic until ready for
reinstallation.
4-107
