1、 FORD LABORATORY TEST METHOD BI 107-01 Date Action Revisions 2001 03 14 Revised Editorial no technical change A. Cockman 1999 02 01 Printed copies are uncontrolled Page 1 of 16 Copyright 2001, Ford Global Technologies, Inc. CHIP RESISTANCE TEST FOR PAINTED PANELS Application This method is used to d
2、etermine the chip resistance of painted panels and body parts and painted plastic panels and parts. Apparatus Required Gravelometer The gravelometer (see Figure 1) consists of an elongated box with a hopper and nozzle system on one end and a slot for the insertion of a test panel on the other end. S
3、teel shot is poured into the hopper where a stream of air propels the shot onto the test panel. The nozzle-system consists, beginning from the main line air supply side of a 200 mm, 12.7 mm air inlet pipe with an inner diameter of 11.5 mm, a tee-piece to fix a pressure gage with a range of 0 to 1.6
4、bars, a 150 mm, 12.7 mm air inlet pipe with an inner diameter of 11.5 mm, and a nozzle which is exactly described in Figure 2. To guarantee a laminar air stream during the test, all pipes have to be polished on the inner surface. From the inlet to the outlet of the air the inner diameter of the pipe
5、 system must be exactly 11.5 mm. The joint from the main line air pressure to the pipe has to be made by a 2 m, 25 mm metal hose. The test air pressure will be adjusted by a ball cock. This cock is fixed behind the main line air pressure gage. This gage has a range of 0 to 16 bars, and it is used to
6、 control the static pressure at closed cock. During the test the flow pressure must be controlled by this gage all the time. A second gage of a range from 0 to 6 bars must be fixed immediately behind the ball cock. By this gage it is possible to control the pressure which is reduced only by the posi
7、tion of the cock. All gages should be calibrated every six months. It is recommended to have a primary pressure of 7 bars. It is not permitted to deviate from the dimensions of these specified components. FORD LABORATORY TEST METHOD BI 107-01 Page 2 of 16 Copyright 2001, Ford Global Technologies, In
8、c. Source: Messrs. Erichsen Pearson-Panke Equipment Ltd. AM Iserback 1-3 Halegrove Gardens 14 D-58675 Hemer London NW7 3LR Germany Tel: 181-959-3232 Tel: 492-372-6431 Fax: 181-959-5613 T.J. Bell Inc. 1340 E. House Ave. Akron, OH 44310 Tel: (888) 393-4975 Fax: (330) 633-1977 Steel Shot 13.6 kg of SAE
9、 780 shot with the following additional requirements: Size: 100 % to pass through a No. 7 screen (2.8 mm) 100 % to be retained on a No. 10 screen (2.0 mm) Shape: To be as near 100 % round as possible Hardness: 90 % to be RC 42-48 Source: Messrs. Nolten Barton Abrasives, Ltd. 4200 Oberhausen George H
10、enry Road Europahaus Great Bridge Germany Tipton, West Midlands DY4 7BS England Steel Test Panels Steel body skin panels 100 x 300 x 0.1 mm (or suitable length for insertion into gravelometer), prepared according to the applicable Engineering Materials Standard. Evaluation Standards Ten black and wh
11、ite photographs as shown in Figure 3 through 12. Source: Central Laboratory Ford-Werke AG D50725 Koln West Germany FORD LABORATORY TEST METHOD BI 107-01 Page 3 of 16 Copyright 2001, Ford Global Technologies, Inc. Calibration of the Gravelometer For calibration of a gravelometer a master nozzle and s
12、pecially prepared calibration panels are required. These panels prepared with three different test enamels which give after shot: rating 10, rating worse than 1 with particular chipping of enamel, and rating worse than 1 with complete chipping, the panels can be obtained from a Global Paint Engineer
13、ing Laboratory. The GPE Laboratory, Cologne is in possession of the master nozzle which can be obtained on request for the calibration exercise. The calibration panels will be tested per Steps 2 through 5 of the procedure as outlined below in the gravelometer to be calibrated. After the procedure re
14、place the complete nozzle system with the master nozzle and repeat the test. If the corresponding panels of both series are equivalent in appearance, the gravelometer may be considered standardized. Note: If it is not possible to achieve equivalent appearance in spite of pressure adjustments accordi
15、ng to Step 4 of the procedure, the procedure system must have a defect or the inner surfaces of the nozzle system are worn out and the failed part must be replaced. Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/
16、- 2 C and 50 +/- 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. Procedure 1. Prepare the test panels with the paint to be tested as specified by the applicable Engineering Material Standard. Test results are extremely se
17、nsitive to total paint film thickness. Thickness determination shall be made on each part tested per FLTM BI 117-01 and recorded. 2. After aging mask off 7.5 cm on each end of the panel and insert the part into the gravelometer as shown in Figure 1. There should be 10 - 15 mm of the upper edge showi
18、ng above the top of the holder. 3. Pour 13.6 kg of shot retained on the No. 10 screen into the hopper with the plug in place. 4. Main line air supply should be at 7 bars prior to and 4.8 - 5.0 bars during the test. Open the line valve and adjust so that air flow through flowmeter indicates a volume
19、of 2.26 m3/minute (0.038m3/s). Note the open line pressure at the indicating gage. This pressure should be 0.5 bar. 5. Pull the plug allowing the shot to fall into the air stream. When the panel has been abraded with the full 13.6 kg of shot, shut off the valve, remove the panel, rinse in warm water
20、 and blot dry. FORD LABORATORY TEST METHOD BI 107-01 Page 4 of 16 Copyright 2001, Ford Global Technologies, Inc. Evaluation Compare the test panel with the standards in Figures 3 through 12 and report the number of the closest comparison panel or evaluate as required by the applicable Engineering Ma
21、terials Specification. 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. FORD LABORATORY TEST METHOD BI 107-01 Page 5 of 16 Copyright 2001, Ford Global Technol
22、ogies, Inc. Figure 1 FORD LABORATORY TEST METHOD BI 107-01 Page 6 of 16 Copyright 2001, Ford Global Technologies, Inc. Figure 2 FORD LABORATORY TEST METHOD BI 107-01 Page 7 of 16 Copyright 2001, Ford Global Technologies, Inc. Rating 10 Figure 3 FORD LABORATORY TEST METHOD BI 107-01 Page 8 of 16 Copy
23、right 2001, Ford Global Technologies, Inc. Rating 9 Figure 4 FORD LABORATORY TEST METHOD BI 107-01 Page 9 of 16 Copyright 2001, Ford Global Technologies, Inc. Rating 8 Figure 5 FORD LABORATORY TEST METHOD BI 107-01 Page 10 of 16 Copyright 2001, Ford Global Technologies, Inc. Rating 7 Figure 6 FORD L
24、ABORATORY TEST METHOD BI 107-01 Page 11 of 16 Copyright 2001, Ford Global Technologies, Inc. Rating 6 Figure 7 FORD LABORATORY TEST METHOD BI 107-01 Page 12 of 16 Copyright 2001, Ford Global Technologies, Inc. Rating 5 Figure 8 FORD LABORATORY TEST METHOD BI 107-01 Page 13 of 16 Copyright 2001, Ford
25、 Global Technologies, Inc. Rating 4 Figure 9 FORD LABORATORY TEST METHOD BI 107-01 Page 14 of 16 Copyright 2001, Ford Global Technologies, Inc. Rating 3 Figure 10 FORD LABORATORY TEST METHOD BI 107-01 Page 15 of 16 Copyright 2001, Ford Global Technologies, Inc. Rating 2 Figure 11 FORD LABORATORY TEST METHOD BI 107-01 Page 16 of 16 Copyright 2001, Ford Global Technologies, Inc. Rating 1 Figure 12
