{"id":9838,"date":"2026-02-24T15:11:44","date_gmt":"2026-02-24T07:11:44","guid":{"rendered":"https:\/\/www.packqc.com\/standard\/astm-d202-2\/"},"modified":"2026-04-16T09:53:05","modified_gmt":"2026-04-16T01:53:05","slug":"astm-d202","status":"publish","type":"standard","link":"https:\/\/www.packqc.com\/nn\/standard\/astm-d202\/","title":{"rendered":"ASTM D202"},"content":{"rendered":"

Coefficient of Friction Testing for Paper<\/h2>\n\n\n\n

Understanding and controlling the coefficient of friction of paper<\/em> is essential for ensuring performance consistency in insulation applications, particularly where paper is used in electrical apparatus. ASTM D202<\/strong><\/a> provides standardized procedures for measuring the surface friction of untreated paper using inclined plane methods. This article will explore the test principle, equipment requirements, testing procedures, and how instruments like the slide angle tester<\/strong> can help meet these standards\u2014while recommending professional-grade solutions like Cell Instruments COF-03<\/a><\/strong> for optimized test performance.<\/p>\n\n\n\n

Importance of Measuring Coefficient of Friction of Paper<\/h2>\n\n\n\n

Friction plays a critical role when paper tapes are used in mechanical or electrical settings. A high or inconsistent coefficient of friction of paper<\/strong> can cause slippage, wrinkling, or poor application during winding or bending operations. The dynamic coefficient of friction<\/strong> determined by ASTM D202 reflects the sliding interaction between two paper surfaces or between paper and smooth metal.<\/p>\n\n\n\n

This data helps manufacturers ensure product reliability during:<\/p>\n\n\n\n

    \n
  • High-speed insulation wrapping<\/li>\n\n\n\n
  • Bending of paper-wrapped conductors<\/li>\n\n\n\n
  • Packaging and lamination processes<\/li>\n<\/ul>\n\n\n\n

    ASTM D202 Testing Procedure Summary<\/h2>\n\n\n\n
      \n
    1. Sample Preparation<\/strong>:
      Cut specimens to required dimensions (e.g., 63\u00d7170 mm and 200\u00d7250 mm), ensuring orientation in machine or cross-machine direction. Identify wire\/felt side and machine direction with markings.<\/li>\n\n\n\n
    2. Conditioning<\/strong>:
      Samples must be conditioned as specified in Section 15 of the standard.<\/li>\n\n\n\n
    3. Test Setup<\/strong>:
      Attach one specimen to the inclined plane and another to the sliding block. Ensure no wrinkles or contamination.<\/li>\n\n\n\n
    4. Preliminary Test<\/strong>:
      Gently raise the plane and tap the block until it slides. Record the preliminary sliding angle.<\/li>\n\n\n\n
    5. Final Test<\/strong>:
      Repeat with a fresh sample and raise the plane to 1\u00b0 less than the preliminary angle. Record the angle at which the block slides without tapping.<\/li>\n\n\n\n
    6. Reporting<\/strong>:
      Report results as the average of at least three measurements. For dynamic coefficient of friction, calculate the tangent of the final friction angle.<\/li>\n<\/ol>\n\n\n\n
      \n