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1、900637=l 0000724 BTO EJ I GENERAL MOTORS ENGINEERING STANDARDS I Materials and Processes - Procedures TEST FOR RAVELING OF NElTlNG GM9543P 1 SCOPE This procedure is used to determine the mla- tive ease or di&ulty with which a diamond shaped knitted net structute will ravel (d&nit). 2 REFERENCED STAN
2、DARDS. None. 3 DEFINITIONS. 3.1 LEG. The branching section of a net structure that forms the diamond shape of the finished product. See Figure 1. 3.2 JOIN. The intersection where the four legs are joined together. See Figure 1. 4 TEST PROCEDURE. 4.1 Cut one leg of the net about midway between hvo jo
3、ins. 4.2 Ravel (deknit) the ends of yarn in the leg down to the join. This is accomplished by gently pulling on the various ends of yam exposed by the cut. 4.2.1 Knit nets will ravel easier in one direction (the last end knit), and will be difficult to ravel in the opposite direction (the first end
4、knit). Use the dim&on which is easier to ravel to continue the test. 4.3 pull firmly on each separate yarn end (one end at a time) while holding the thme remaining legs behind the join in the opposite hand 4.4 Note whether or not any of the yarn ends can be pulled through the join and begin to ravel
5、 one of the three legs held in the opposite hand 4.5 Repeat steps 4.1 through 4.4 at two more locations on the net. 5 EVALUATION AND RESULTS. 5.1 The three tested areas should each be rated using the fol- lowing scale. 5.1.1 Ravels easily. One of the yarns can be easily pulled through the join and r
6、avels into another leg readily. 51.2 Ravels with some msistance. One of the yarns ravels thtmgh the join and into another leg, but resists raveling eas- ily. The yarn must be pulled firmly to cause the raveling into another leg. 51.3 Strongly resistant to raveling. Another leg can be made to begin t
7、o ravel only when an individual yarn end is pulled through the joint with maximum effort. 51.4 Does not ravel. None of the individual yarns can be pulled through the join to cause raveling of another leg using maximum force by hand 6 6.1 6.2 6.3 6.4 REPORT. The report should include the following: C
8、omplete identification of the net. Conditioning of test specimen, if any. Test conditions, temperatum, humidity, etc. Test results, per above rating scale, with any observa- tions. 7 SAFETY. This method may involve hazardous materi- als, operations and equipment. This method does not propose to addr
9、ess all the safety problems associated with its use. It is the responsibility of the user of this method to establish appro- priate safety and health practices and determine the applicability of regulatory limitations prior to use. 8 GENERAL INFORMATION. This standard was origi- nated by the Textiles Committee in April 1993 and approved in June 1993. JULY 1993 PAGE 1 9!543P 7006379 0000725 737 EI I GENERAL MOTORS ENGINEERING STANDARDS I Materials and Processes - Procedures I TEST FOR RAVELING OF NElTING GM9543P JOIN JOIN LEG LEG PAGE 2 JULY 1993