1、 FORD LABORATORY TEST METHOD BV 127-02 Date Action Revisions 2003 05 22 Activated A. Reaume Printed copies are uncontrolled Page 1 of 2 Copyright 2003, Ford Global Technologies, Inc. SKIN-OVER TIME OF RTV SEALANTS Application This method is used to determine the skin over (open time) for RTV sealant
2、s. The method applies to both self-leveling and thixotropic materials. Equipment Required 1. Aluminum weighing dish, 57.2 mm diameter. 2. Laboratory Balance: 1 mg accuracy 3. Glass plate 4. Spatula, stainless steel 102 mm long x 6 mm wide. 5. Laboratory timer: 0.1 second accuracy Procedure 1, Self-l
3、eveling materials 1. Weigh 3.0 grams of product into an aluminum weighing dish. Gently tip the dish side to side to evenly coat the bottom of the dish. 2. Start the timer. 3. When the product begins to skin, touch the surface using light finger pressure, every 1 minute and check for material transfe
4、r to the spatula. If the material has skinned at the first test, repeat the procedure using a new sample and start testing earlier. Clean the spatula with an appropriate solvent, and dry with a towel, between tests 4. Stop the timer when the product no longer transfers to the spatula. 5. Report this
5、 time as the skin over time. FORD LABORATORY TEST METHOD BV 127-02 Page 2 of 2 Copyright 2003, Ford Global Technologies, Inc. Procedure 2, Thixotropic materials 1. Dispense a 50 x 6.4 mm sample of the product onto a glass plate. 2. Start the timer. 3. When the product begins to skin, touch the surfa
6、ce using light finger pressure, every 1 minute and check for material transfer to the spatula. If the material has skinned at the first test, repeat the procedure using a new sample and start testing earlier. Clean the spatula with an appropriate solvent, and dry with a towel, between tests 4. Stop
7、the timer when the product no longer transfers to the spatula. 5. Report this time as the skin over time. Report Report the skin-over time to the nearest minute. Chemicals, materials, parts, and equipment referenced in this document must be used and handled properly. Each party is responsible for determining proper use and handling in its facilities.
