Q10-12. What is the service life of a synthetic rubber
Q10-7. How are locally fabricated hose assemblies
hose assembly that is exposed to the weather,
identified?
fuel, or heat?
Q10-8. What type of cover is used to protect a hose
assembly that is subjected to high
temperatures?
TUBING ASSEMBLIES
Q10-9. All hose assemblies manufactured in a shop
must have what test completed before they are
LEARNING OBJECTIVES: Identify the
installed on an aircraft?
various types of tubing and tubing assemblies.
Recognize materials, tools, equipment, and
Q10-10. What is the first thing you must do when you
testing procedures used in tubing assemblies.
discover a swivel nut leaking?
Recognize maintenance procedures for tubing
Q10-11. What is the acceptance life for a synthetic
assemblies.
rubber hose assembly?
Table 10-9.--Corrosion-Resistant Steel Tubing
Specification
Type
Condition
General Usage and Applications
Tubing Material
MIL-T-7081
6061 A1
Specification covers annealed and three heat-treated
tempers used mostly in O-annealed and T-6. Has
good workability. The 6061-T6 is used in
hydraulic/pneumatic 3000-psi systems.
MIL-T-8506
304
Annealed
Low-pressure applications such as fuel lines.
18-8
Unsatisfactory for high-pressure hydraulic lines. Has
Corrosion-Resistant Steel
high degree of resistance to corrosion.
(CRES)
MIL-T-8504
304
Annealed
Unsatisfactory for welding, brazing or exposure to
temperatures higher than 800F. Used in high-pressure
18-8
CRES
hydraulic/pneumatic systems.
304L
MIL-T-8606
Annealed
Hydraulic/mechanical applications. Has high resistance
to corrosion and high temperatures up to 1500F.
(low carbon)
18-8
321
CRES
Suitable for applications requiring welding/brazing.
347
Type II intended for high-pressure hydraulic
applications, using brazed sleeve joints.
MIL-T-6845
304
1/8H
Used in high-pressure hydraulic/pneumatic systems.
18-8
Unsuitable for welding/brazing applications or
exposure to temperatures above 800F.
CRES
MIL-T-8973
304L
1/8H
Used in high-pressure hydraulic/pneumatic systems
18-8
(low carbon)
assembled with brazed sleeve joints. Suitable for use in
316L
CRES
moderately corrosive or oxidizing environments,
temperatures to 1200F. Weldable.
(low carbon)
321
347
MIL-T-5695
304
1/4H
Used for aircraft structural parts or similar applications
18-8
not requiring sharp bends or flaring. Unsatisfactory for
1/2H
CRES
welding other than resistance weld.
321
Annealed
MIL-T-8808
Aircraft hydraulic quality, used in high-pressure
hydraulic/pneumatic systems. Most often used in these
347
18-8
systems requiring brazing/welding.
CRES
10-24
