1、 FORD LABORATORY TEST METHOD BV 126-01 Date Action Revisions 2000 12 11 Revised Editorial no technical change A. Cockman 1992 04 23 Printed copies are uncontrolled Page 1 of 4 Copyright 2000, Ford Global Technologies, Inc. BLOW-OUT RESISTANCE OF ONE COMPONENT SEALANTS Application This test method wi
2、ll determine the resistance of a one component sealant, to resist blow-out at specified pressures and gap widths. Apparatus Required Test Fixture - see Figures 1 through 3. Note: Detail drawings of the test fixture are available from the Product and Manufacturing Engineering Staff office. Air Supply
3、 and Regulator Accurate to within +/- 0.7 kPa Cleaning Solvent Stop Watch or Timer Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/- 2 C and 50 +/- 5 % relative humidity for not less than 24 h prior to testing and
4、 tested under the same conditions unless otherwise specified. Procedure 1. With the outlet valve closed, seal off the center cavity of the fixture base and adjust the air pressure on the gauge to 17.2 kPa. Then open the outlet valve. 2. Remove all traces of cured and uncured sealant from the fixture
5、 (base, top, joint faces, and center cavity). 3. Place the fixture top on the bench with the cavity facing upward. Dispense a portion of the test sealant in the center of the cavity large enough to amply fill the cavity when screeded flush (see Figure 2). FORD LABORATORY TEST METHOD BV 126-01 Page 2
6、 of 4 Copyright 2000, Ford Global Technologies, Inc. 4. Use a 25 x 75 x 0.8 mm aluminum test panel as a scraper to compress the sealant into the cavity. Place the scraper at the center of the cavity at a 45 angle and slowly screed the sealant flush with the surface of the fixture cavity. Repeat in t
7、he opposite direction. The sealant surface must be flush or no more than 2.5 mm higher than the fixture surface. Avoid having the sealant surface concaved. 5. Check to be sure the outlet valve is open and carefully place the fixture top over the 3 studs on the fixture base and gently lower into plac
8、e (see Figure 3). 6. Assemble the wing nuts and hand tighten. Close the outlet valve. 7. Crank open the inlet valve and start timing simultaneously. As soon as the pressure reaches 17.2 kPa, close the inlet valve. 8. If pressure begins to decay from the stable 17.2 kPa, a leak is indicated. Stop the
9、 timing. Normally the gauge needle will drop back to zero very abruptly. Record the number of seconds elapsed to blow-out. 9 If blow-out does not occur in 60 s, report blow-out as being greater than 60 s. Chemicals, materials, parts, and equipment referenced in this document must be used and handled
10、 properly. Each party is responsible for determining proper use and handling in its facilities. FORD LABORATORY TEST METHOD BV 126-01 Page 3 of 4 Copyright 2000, Ford Global Technologies, Inc. BLOW-OUT RESISTANCE OF ONE COMPONENT SEALANTS Figure 1 Figure 2 FORD LABORATORY TEST METHOD BV 126-01 Page 4 of 4 Copyright 2000, Ford Global Technologies, Inc. BLOW-OUT RESISTANCE OF ONE COMPONENT SEALANTS Figure 3