1、GM DAEWOO Auto & Technology EDS Engineering, GM DAEWOO Auto & Technology Standards TEST METHOD FOR DETERMINING THE METLING RANGE OF PLASTIC MATERIALS EDS-T-7505 ISSUED DATE: 1993. 07. 13 REVISED DATE: 2006. 06. 19 VERSION: 3 EDS-T-7505TEST METHOD FOR DETERMINING THE METLING RANGE OF PLASTIC MATERIAL
2、S PAGE: 1/3 ISSUED DATE: 1993. 07. 13 REVISED DATE: 2006. 06. 19 VERSION: 3 GM DAEWOO Auto & Technology 1. PURPOSE The purpose of this standard is to determine the melting range of plastic films, molded parts and the coatings on leather cloths etc. 2. SCOPE This standard shall specify the method for
3、 determining the melting range of the plastic materials. The melting range is indicated by the “variance“ of melting point determinations carried out on several representative test pieces. 3. TEST PIECES 3.1. Size of test pieces: The test pieces of (702)mm(50.5)mmthickness shall be taken from variou
4、s areas of available material but no closer than 100mm to an edge. Test pieces shall, wherever possible, be taken along a warp thread and along a weft thread or in longitudinal and transverse directions. For test samples in the form of strips, or narrow mouldings of width less than 10mm, the test pi
5、eces shall be taken in the longitudinal direction only. 3.2. Number of test pieces 3.2.1. For initial sample approval and arbitration purposes : at least 3 3.2.2. For routine quality control : at least 3 3.3. Sample of components or materials released to this specification shall be tested for confor
6、mity with the requirements of this specification and approval by GMDAT TECHINICAL CENTER prior to commencement of delivery of bulk supplies. 4. CONDITIONING For initial sample approval and arbitration purposes, conditioning shall be carried out according to EDS-T-7507. 5. APPARATUS 5.1. Heating Appa
7、ratus A heating device, providing a differentially heated surface plate and temperature scale fitted with an adjustable pointer, capable of calibration, shall be used. A suitable apparatus is a Kofler heating device manufactured by Messer Reichert Vienna, and illustrated in Fig.1. This apparatus con
8、sists of a rectangular surface plate (1) which is electrically heated at one end, providing a thermal gradient along the longitudinal direction. Temperature is indicated on the scale (2) via a pointer (4) which is connected to a sliding guide block (3) through an adjustable slider (5). EDS-T-7505TES
9、T METHOD FOR DETERMINING THE METLING RANGE OF PLASTIC MATERIALS PAGE: 2/3 ISSUED DATE: 1993. 07. 13 REVISED DATE: 2006. 06. 19 VERSION: 3 GM DAEWOO Auto & Technology Figure 1. Heating apparatus 5.2. Calibration media A set of heat sensitive crayons, paints or powders dividing into the appropriate te
10、mperature range. 5.3. Chamber capable of for conditioning to of clause 4. 5.4. Cutting dies or shears for preparation of test pieces. 6. PROCEDURE 6.1. The test shall be performed immediately after conditioning or in the as received condition. 6.2. Calibration of heating apparatus: Since this appara
11、tus can be considerably influenced by its surrounding environment, it is essential that it shall be operated in a wind free location, having a constant ambient temperature within the temperature range of +235K.This apparatus shall be calibrated as follows prior to use. 6.2.1. The apparatus shall be
12、allowed to run for approximately 1 hour to achieve temperature stability. 6.2.2. A small quantity of the calibration medium(of melting point similar to that expected of test piece being tested) shall be applied to the surface plate so as to from a line in the longitudinal direction across the approp
13、riate temperature zone. 6.2.3. After sufficient time has elapsed for melting to occur, the sliding guide block shall be adjusted such that the pointer corresponds with the dividing line between melted and not melted calibration medium, and the slider adjusted such that the temperature indicated on t
14、he scale corresponds with the melting point of the calibration medium selected. EDS-T-7505TEST METHOD FOR DETERMINING THE METLING RANGE OF PLASTIC MATERIALS PAGE: 3/3 ISSUED DATE: 1993. 07. 13 REVISED DATE: 2006. 06. 19 VERSION: 3 GM DAEWOO Auto & Technology 6.2.4. Ambient temperature shall be recor
15、ded during calibration. If this alters during subsequent tests, then re-calibration shall be carried out. 6.3. Determination of melting range 6.3.1. The test piece shall be placed on the heated surface plate at the appropriate approximate position, so as to be parallel to the heating plate. Coated a
16、nd laminated test pieces shall then have the plastic side downwards. 6.3.2. After a period of 3 seconds, the test piece shall be eased away from the heated plate, using a rolling motion as shown in Fig. 2, starting from the cooler end, and taking care that no pressure be applied to the test piece. F
17、igure2. Form of test piece 7. EVALUATION AND EXPRESSION OF RESULTS 7.1. The melting range shall be expressed as the minimum and maximum values of melting points obtained from each test piece. 7.2. The melting range shall be noted in . 8. CODING SYSTEM On drawings, material specifications etc., the m
18、elting range shall be indicated as follows. MELTING RANGE to EDS-T-7505 +128135 Designation Test method Requirement 9. REFERRENCE EDS-T-7507 Test method for conditioning of plastic materials, textiles, fiberboards wood etc. GME 60308 Test method for determining the melting range of plastic materials
