MIL-DTL-24695C(SH)
3.3 Materials.
3.3.1 Compatibility. Where specified herein, parts shall be constructed of materials that are compatible with
the following hydraulic service fluids: MIL-PRF-17672, MIL-H-19457, MIL-H-22072, and MIL-PRF-17331
(see 3.3.6 and 3.3.7). Verification of material compatibility shall be by analysis or test (see 4.2.6).
3.3.2 Prohibited materials. The following materials shall not be used:
a.
Toxic materials.
b.
Zinc or zinc plated materials.
c.
Mercury.
d.
Magnesium or magnesium base alloys.
e.
Radioactive materials.
f.
Asbestos.
g.
Cadmium plated materials.
h.
Beryllium.
i.
Hexavalent Chromium.
3.3.3 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally
preferable materials should be used to the maximum extent possible, provided that the material meets or exceeds the
operational and maintenance requirements, and promotes economically advantageous life cycle costs.
3.3.4 Nickel alloys. Nickel alloys for use in pressure containing vent and test valve, hose assembly, or adapter
parts shall be limited to nickel-copper (NiCu) alloy: QQ-N-281, Class A (see 4.2.3.1, 4.2.4.1, and 4.2.5.1).
3.3.5 Corrosion resistant steel (CRES). The use of chromium-nickel austenitic steel in pressure containing vent
and test valve, hose assembly, or adapter parts shall be limited to Class 304, 304L, 316, or 316L in accordance with
SAE AMS-QQ-S-763; Type 316Ti in accordance with ASTM A276; or other steel as approved by the qualifying
3.3.6 Non-metallic materials. Vent and test valve cap, if fabricated from non-metallic materials, shall be
compatible with all hydraulic service fluids specified herein (see 3.3.1). Hose assembly parts fabricated from
non-metallic materials shall be compatible with all hydraulic service fluids specified herein (see 3.3.1).
3.3.7 O-rings. Internal O-ring seals shall be compatible with all hydraulic service fluids specified herein
(see 3.3.1) or shall be in accordance with SAE AS3581 (see 4.2.3.1 and 4.2.5.1). External O-ring seals shall be
fluorocarbon elastomer in accordance with SAE AS3581 and shall be provided with the valve (see 4.2.3.1).
3.4 Construction.
3.4.1 Vent and test valves. Vent and test valves shall be constructed as specified herein and in the applicable
specification sheet. The vent and test valves furnished under this specification shall seal by means of a spring
loaded check valve. A probe, integral to the end fitting of the hose assembly and conforming to the configuration
identified in the applicable specification sheet, shall be used to open the check valve by depressing the ball or
poppet, opening the flow passage. When specified by the specification sheet (see MIL-DTL-24695/1) part number
designation, a lock wire hole on the hex portion of the valve shall be provided in accordance with the specification
sheet.
3.4.1.1 Strength. Vent and test valves shall withstand the structural loads imposed by the test requirements of
this specification. Valves shall withstand the wrench loads required for installation. The use of aluminum alloys for
threaded applications is prohibited.
3.4.1.2 Clearance. Within the most adverse dimensions, there shall be clearance of moving parts at 0 and at
70 °C (32 and at 158 °F). The room temperature reference point shall be 20 °C (68 °F).
3
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business