1、GM DAEWOO Auto & Technology EDS Engineering, GM DAEWOO Auto & Technology Standards METHOD OF FLATTENING TEST FOR METALLIC TUBE EDS-T-7116 ISSUED DATE: 1993. 07. 13 REVISED DATE: 2006. 06. 19 VERSION: 2 EDS-T-7116METHOD OF FLATTENING TEST FOR METALLIC TUBE PAGE: 1/2 ISSUED DATE: 1993. 07. 13 REVISED
2、DATE: 2006. 06. 19 VERSION: 2 GM DAEWOO Auto & Technology 1. PURPOSE This standard aims at helping test personnel perform the tests in an appropriate method by describing the method of flattening test for judging formability of metallic materials. 2. SCOPE This standard is applicable to seam tube(we
3、lded tube) and seamless tubes with circular cross-section. Sizes of applicable tubes are as follows. Table 1. The material and size of applicable tube Material Outside diameter of tube (mm) Steel 400 max. Aluminum and aluminum alloy 150 max. Copper and copper alloy 100 max. 3. DEFINITION OF TERMINOL
4、OGY 3.1. Welded tube: Cylindrical molded product whose seam parts are welded or roll welded. 3.2. Seamless tube: A tube without seam that is manufactured either by hot rolling, extrusion and drawing or by machine finishing after piercing. 4. TEST PIECE 4.1. A test piece 50mm or over in length shall
5、be cut off from the end of a tube. For the tube whose wall thickness is 15% or over of its outside diameter, C type test piece (b of Fig. 1) made by removing part of the circumference of a whole test piece may be used. 4.2. Cut section shall be vertical to the tube length direction and shall not be
6、sharp. 5. TEST MACHINE Test machine which has two hard pressure plates in parallel or press bias etc shall be used. In this case, the length and width of pressure plate shall be more than 1.6 times the length of the tube after flattening test and outside diameter. 6. TEST METHOD 6.1. Pinch the test
7、piece between two flat plates of test machine. Especially, in case of welded tube, install it so that welded portion may be placed in the center of upper and lower flat plates. EDS-T-7116METHOD OF FLATTENING TEST FOR METALLIC TUBE PAGE: 2/2 ISSUED DATE: 1993. 07. 13 REVISED DATE: 2006. 06. 19 VERSIO
8、N: 2 GM DAEWOO Auto & Technology Fig. 1. Flattening Test 6.2. Compress flat plate of test machine by applying appropriate pressure until the distance between flat plates comes to the specified value in the standard. At this time, the speed of flat plate shall not exceed 25mm/min. 6.3. Check the cond
9、ition of test piece by removing it from the test machine. 7. EVALUATION Inspect the condition of test sample after the test visually or with suitable inspection device (a magnifying glass, three-dimensional microscope). At this time, test sample shall be free from defects such as cracks, burst and f
10、laws. 8. INDICATION METHOD The following items shall be recorded in the test report. 8.1. Material of tube, outside diameter, wall thickness 8.2. Welding position between flat plates at the time of test 8.3. Pressure speed of flat plate 8.4. Distance of flat plate 8.5. Condition of test piece after
11、the test 9. REFERENCE KS D 3517 Carbon steel tubes for machine structural purposes JIS G 3445 Carbon steel tubes for machine structural purposes DIN 50136 Testing of metals - flattening test on tubes ASTM A 530 Standard specification for general requirements for specialized carbon & alloy steel pipes IS0 8492 Metallic materials - tube - flattening test
