Wetting time shall be not less than 0.5 second, if the
wet-winding process is used.
A Prony-brake device or an eddy-current brake device or
equivalent device shall be used to maintain the proper
tension in the glass roving during winding.
Process controls. A rigid process control shall be
established and maintained to ensure compliance with the following
Completely impregnated roving.
Average resin content of the full wall thickness at any
Resin content of not
point, between 17 and 30 percent.
less than 15 percent in any sample (see 4.6.12).
Filament tension schedule such that the Inner plies of the
glass filaments (roving) are not deformed out of their
initial configuration by succeeding plies of roving.
Void content. Void content shall not exceed an average of
7 percent for all determinations on any cylinder when tested as specified
Void content for any single determination shall not exceed 8
Metal coating and assembly. All surfaces of the liner not
covered with fiberglass laminate shall be coated with MIL-C-5541 chemical
After treatment is air dry, the port fitting shall be assembled
into the cylinder opening with `On-ring seal equal to C. E. Conover and
Company part number 3-912, and tightened to a torque of 360 to 420 inch-
pounds (in-lb). Within 10 hours of application of the MIL-C-5541 treat-
ment, exterior metal surfaces (not inside screw threads) on the blank end
of the cylinder and on the port end, including the port fitting up to
approximately 1/16 inch onto the wrench flats, shall be coated with
MIL-P-23377 material to a dry film thickness of 0.5 mil to 0.75 roil, (if
10 hours is exceeded the surfaces shall be solvent cleaned immediately
prior to the MIL-P-23377 application).
Within 24 hours of application
of MIL-P-23377 material, the coated metal surfaces shall be given two coats
of formula 151 (gray) of MIL-P-24441/2.
Each coat shall be 6 to 8 roils
dry film thickness.
At the port end, the objective is to coat exposed
aluminum and to continue the coating, as a heavy fillet onto the port
fitting, but leaving the major area of the wrench flats and outer end
Drying time between coats shall be no less than 6 hours or
until a "tack free" state is achieved.
Barrier coating. A transparent moisture-barrier coating
shall be applied to the exterior surface of the cylinder.
shall be sufficiently flexible to resist crazing, cracking. blistering
or separation during pressure and environmental testing required herein.
Volume (for internal volumes, see 188.8.131.52). Volume shall
be determined after the volumetric expansion test (see 4.6.1).
3.2.8 Structural strength. The cylinder shall have ample strength
and rigidity to withstand 250 percent of maximum wrench torques as .
specified in 184.108.40.206 without permanent deformation of the cylinder.