【国外标准】 Standard Test Methods for Polytetrafluoroethylene Tubing

4.1 The test methods in this standard are considered important to characterize polytetrafluoroethylene tubing. They are intended primarily for, but not limited to polytetrafluoroethylene tubing.4.2 Variations in these methods or alternate contemporary methods of measurement may be used to determine the values for the properties in this standard provided such methods ensure quality levels and measurement accuracy equal to or better than those prescribed herein. It is the responsibility of the organizations using alternate test methods to be able to demonstrate this condition. In cases of dispute, the methods specified herein shall be used.NOTE 2: Provision for alternate methods is necessary because of (1) the desire to simplify procedures for specific applications, and (2) the desire to eliminate redundant testing and use data generated during manufacturing process control, including that generated under Statistical Process Control (SPC) conditions, using equipment and methods other than those specified herein. An example would be the use of laser micrometers or optical comparators to measure dimensions.1.1 These test methods cover procedures for testing polytetrafluoroethylene tubing for use as electrical insulation. The procedures appear in the following sections:   Procedure  Sections   ASTM  Methods     Conditioning  7 ...Dielectric Breakdown Voltage 28 – 30 D149, D876Inside Diameter  8 – 13 D876Mandrel Bend Test 46 – 52 D149, D876Melting Point 41 – 45 D3418, D4895Penetration Test 26 and 27 D876Specific Gravity 36 – 40 D792, D1505Strain Relief 31 – 35 ...Volatile Loss 20 – 25 ...Wall Thickness 14 – 19 ...NOTE 1: These test methods are similar but not identical to those in IEC 60684–2.1.2 The values stated in inch-pound units are the standard except for temperature, which is stated in degrees Celsius. Values in parentheses are for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see Section 5.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.