26 September 2006
Hydraulic test systems must comply with the following:
For hydraulic systems that use pressures exceeding 1380 kPa (200
psi), SAE 1010 dead-soft, cold-drawn, seamless-steel tubing (or equivalent) must
be used. A factor of safety of eight over normal working pressure must be used.
For systems with working pressures in excess of 17,240 kPa (2,500 psi), a factor
of safety of four over normal working pressure is acceptable. Tubing is
preferable to pipe. Tubing can be bent to fit in restricted spaces with a minimum
number of fittings, reducing the number of possible leakage points. Solderless,
steel fittings of the flareless "locking-sleeve" type or flare type must be used.
Use of threaded pipe should be avoided. Where threaded
connections are used, requirements of ANSI B1.20.1 Pipe Thread must be met.
A safety factor of eight over maximum normal pressure must be used.
Tubing runs must have as few bends as possible, but should have
at least one bend to provide for thermal expansion and contraction. The
minimum radius of tube bend must be three tube diameters.
Where hose must be used for flexible connections, it must be steel
reinforced, designed for the hydraulic fluid being used, and capable of
withstanding five times the actual operating pressure. Hose couplings and
fittings and minimum bending radius must be in accordance with the hose
manufacturer's instructions. Hose must be installed so as not to rub against
objects as a result of machine movement, vibration, or pressure surges.
Piping and tubing must be anchored or secured to minimize failure
due to vibration. Pipe supports must not prevent normal thermal expansion.
There must be an accessible, well-marked, emergency shutoff
switch for each pump.
Provide automatic shutoff switch to deactivate hydraulic pump upon
loss of pressure.
Requirements listed in this section are applicable to both fixed wing and rotary
wing aircraft for fuel cell maintenance facilities, corrosion control and protective
coating, and general-purpose maintenance hangars. These criteria apply to new
hangars, the renovation or modernization of existing hangars, and permanent
Tension Fabric Hangars. The passive fire protection and life safety requirements
must comply with NFPA 101 and NFPA 409, Standard on Aircraft Hangars.
Note 1: For Air Force projects, refer to Air Force ETLs for requirements.