MIL-S-7916 SEALING COMPOUND, THREAD AND GASKET, FUEL, OIL, AND WATER RESISTANT S/S BY SAE-AS-S-7916SEALING COMPOUND, THREAD AND GASKET, FUEL, OIL, AND WATER RESISTANT S/S BY SAE-AS-S-7916

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MIL-S-7916D

removed by dipping the specimens in water.  The specimens shall then be oven dried for 22 ± 0.25 hours at 70° ± 1°C (158° ± 2°F).  After removal from the oven, the specimens shall be cooled to room temperature by placing them in a desiccator for at least one hour before reweighing.  Tests shall be run in triplicate.  Percent change in weight shall be calculated as follows:

C3  - C2

% weight change =  ------------   x  100

C2  - C1

Where   C1  = Weight of panel

C2  = Weight of panel + sealing compound before immersion

C3  = Weight of panel + sealing compound after immersion.

4.5.2  Seal-breaking torque.

4.5.2.1  Test fittings.  Three hydraulic fitting assemblies comprised of an AN815-8D union flared tubing and AN817-8D nut-sleeve coupling shall be utilized for this test.

4.5.2.2  Procedure.  The sealing compound shall be brushed onto the threads of a clean union in sufficient quantity to fill the threads evenly, then assembled with the nut and tubing.  After assembly is completed, excess compound which has extruded shall be wiped from the flange.  The assembly shall be tightened to 200 inch-pounds of torque and then exposed in a

circulating oven for 7 days at 70° ± 1°C (158° ± 2°F).  After removal from the oven, excess compound on the outer edge of the joint shall be removed by scraping, then place the assembly in a desiccator for 24 hours.  The torque

required to break the seal shall be determined with the same wrench used to assemble the fitting.

4.5.3 Flow (vertical).

4.5.3.1  Test panels.  Two panels, approximately 2.5 by 15 cm (1 by 6 inch) shall be prepared from aluminum alloy conforming to QQ-A-250/4-T3.  One panel shall be bare, the other anodized in accordance with MIL-A-8625.  Each panel shall be coated over a 2.5 by 5 cm (1 by 2 inch) section with a 1.6 mm (0.063 inch) thick coating of sealing compound.  A scribe line shall bve made on the uncoated portion of surface of the metal 0.25 inch below the compound.

4.5.3.2  Procedure.  Immediately after coating, the panels shall be placed in a vertical position with the scribe line at the bottom of the panel and allowed to stand in this position for one hour at 21° to 27°C (70° to 80°) to determine the flow of the compound in reference to the scribe line.

4.5.4  Non-volatile content.  Three to five grams of the compound shall be placed in an accurately weighed flat bottom metal dish having a diameter of about 8 cm.  The dish and sample of compound shall be weighed and placed in a circulating air oven, maintained at 70° ± 1°C (158° ±  2°F), for 46 ± 0.25 hour.  The percent non-volatile content shall be calculated as follows:

W2

Non-volatile content =   ---   x  100

W1

Where:  W1  = Weight of original sample

W2  = Weight of residue

4.5.5  Accelerated storage stability.  A one quart sample of the

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