1、 FORD LABORATORY TEST METHOD BS 151-02 Date Action Revisions 2000 11 10 Revised Editorial no technical change A. Cockman 1991 03 13 Printed copies are uncontrolled Page 1 of 3 Copyright 2000, Ford Global Technologies, Inc. DETERMINATION OF FORM STABILITY Application This procedure is used to determi
2、ne the form stability of cellulose fibre type boards, e.g. hardboards, pulp molded fibre boards, under different climatic conditions. Apparatus Required Humidity Cabinet Cap able of maintaining a constant temperature of 38 +/ - 2 C and 98 +/ - 2 % relative humidity. Oven Mechanically convected, capa
3、ble of maintaining a constant temperature of 90 +/ - 2 C. Metal Bars Mild steel, 180 mm long, approximately 40 mm wide, and appro ximately 5 mm thick and treated against corrosion, e.g. painted. Screw Clamps Slide Gauge Conditioning and Test Conditions All test values indicated herein are based on m
4、aterial conditioned in a controlled atmosphere of 23 +/ - 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. Cut two test specimens 180 mm x 200 mm in size from both the longitudinal and transver
5、se directions. 2. Mount the sp ecimens as shown in Figure 1 on the metal bars using two screw clamps. Ensure that the nearest distance between the edges of the two clamps is exactly 150 +/ - 0.5 mm. 3. Subject the specimens successively to the following tests: FORD LABORATORY TEST METHOD BS 151-02 P
6、age 2 of 3 Copyright 2000, Ford Global Technologies, Inc. A. Humidity Test 1. Su spend the specimen in vertical position in the humidity cabinet at 38 +/ - 2 C and 98 +/ - 2 % relative humidity for 16 hours. 2. Remove the specimen, measure the maximum height of warp. The measurement must be done wit
7、hin 30 minutes using a slide gauge. 3. Calculate the percentage of form stability as follows, computing the average value of the 4 specimens: Form stability (%) = max height x 100 (after humidity test) 150 B. Heat Test 1. Place the same specimen in the convection oven at 80 + / - 2 C for 6 hours. 2.
8、 Remove the specimen, allow to cool to room temperature and measure as described in (A) above. 3. Calculate the percentage of form stability after heat test as in (A). C. Conditioning in Standard Atmosphere 1. Condition the same specimen - already used for the humidity and heat - storage - at 23 +/
9、- 2 C and 50 +/ - 5 % relative humidity for 24 hours. 2. Measure the height of warp and calculate form stability after conditioning as in (A). 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 BS 151-02 Page 3 of 3 Copyright 2000, Ford Global Technologies, Inc. DETERMINATION OF FORM STABILITY Figure 1
