1、GM DAEWOO Auto & Technology EDS Engineering, GM DAEWOO Auto & Technology Standards METHOD OF TRANSVERSE BENDING TEST OF GRAY CAST IRON EDS-T-7129 ISSUED DATE: 1990. 11. 20 REVISED DATE: 2006. 06. 19 VERSION: 2 EDS-T-7129METHOD OF TRANSVERSE BENDING TEST OF GRAY CAST IRON PAGE: 1/2 ISSUED DATE: 1990.
2、 11. 20 REVISED DATE: 2006. 06. 19 VERSION: 2 GM DAEWOO Auto & Technology 1. PURPOSE This standard aims at measuring mechanical properties of gray cast iron conveniently by measuring transverse bending deflection strength from cylindrical test piece as cast. 2. SCOPE This standard specifies the tran
3、sverse bending test method of gray cast iron. 3. TEST PIECE 3.1. In principle, the test piece shall be used as cast. The surface may be machine - finished to meet the dimensional requirement within the tolerance range. 3.2. The test piece shall be cylindrical cast, and its standard dimensions shall
4、be divided as follows. Table 1 Type of test piece Diameter as cast D (mm) Diametric tolerance (mm) Length between fulcrums L1(mm) Length of test piece L2(mm) a 20 1.0 200 300 b 30 1.0 300 350 c 30 1.5 450 500 d 45 2.0 600 650 4. TEST METHOD 4.1. Place the bending tool (supports, pressurizing metal f
5、itting) on the tensile testing machine as shown in Fig. 1. S: Supports P: Pressurizing metal fitting T: Test piece Fig. 1 S SP DL2L1L1/2 L1/2LoadEDS-T-7129METHOD OF TRANSVERSE BENDING TEST OF GRAY CAST IRON PAGE: 2/2 ISSUED DATE: 1990. 11. 20 REVISED DATE: 2006. 06. 19 VERSION: 2 GM DAEWOO Auto & Te
6、chnology 4.2. Here, the supports and pressurizing metal fitting shall point-contact with the test piece and their diameters shall be 6.4 25.4mm. 4.3. Place the test piece on the two supports and apply the load to the test piece in transverse direction until it breaks using pressurizing metal fitting
7、 that is placed on the central part of the test piece. 4.4. Examine the maximum load and deflection when it breaks. 4.5. In case the diameter of the test piece is within the tolerance specified in Table 1 and less than nominal dimensions, the maximum load can be compensated according to the followin
8、g formula. Po = P (Do / D)3Po : Compensated maximum load(kgf) P : Measured maximum load(kgf) Do : Nominal diameter of the test piece D : Measured diameter of the test piece 5. NOTE 5.1. When there is a defect on the surface of the test piece, it shall be discarded and replaced with new one before th
9、e test. 5.2. When the defect in the test piece is detected after the test, the test shall be nullified if it is judged that the defect influenced the test result. 5.3. The test piece and the supports shall be placed at the central portion of the pressurizing metal fitting. The testing personnel shal
10、l be cautious of his safety as the cut test piece may fall. 5.4. The load shall be increased at a rate not exceeding 3 kgf/mm2a second without abrupt change until it breaks. 6. REFERENCE ASTM A 438 Standard method for transverse testing of gray cast iron DIN 50110 Testing of gray cast iron (transverse bending test) KS B 0808 Transverse test specimen for metals KS D 4301 Gray iron castings
