1 Scope
This part of GB/T 22471 specifies the test method of resin impregnated glass banding tape for electrical insulation (hereinafter referred to as banding tape).
This part is applicable to the performance test of semi-cured (Stage B) banding tape.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this part of GB/T 22471. For dated references, subsequent amendments (excluding corrections), or revisions, of any of these publications do not apply to this part. However, parties to agreements based on this part are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest editions apply to this part.
GB/T 1408.1-2006 Electrical strength of insulating materials—Test methods—Part 1: Tests at power frequencies (IEC 60243-1:1998, IDT)
GB/T1411-2002 Dry, solid insulating materials—Resistance test to
high-voltage, low-current arc discharges (IEC 61621:1997, IDT)
GB/T 4207-2003 Method for determining the comparative and the proof tracking indexes of solid insulating materials under moist conditions
GB/T 11026.1-2003 Electrical insulating materials—Properties of thermal endurance—Part 1: Ageing procedures and evaluation of test results (IEC 60216-1:2001, IDT)
3 General requirements for test
Unless otherwise specified, the specimens shall be treated at (23±2)°C and (50±5)% relative humidity for 24 h and tested under this condition.
For the high temperature test, it shall be treated at the specified temperature for 45 min before the test.
4 Width
With a steel ruler with a dividing value of 0.5 mm, measure one point at intervals of about 300 mm along the length direction of the banding tape, and measure the width of five points in total, taking the median value as the test result.
5 Thickness
With a spiral micrometer with a dividing value of 0.01 mm, measure one point at intervals of about 300 mm along the length direction of the banding tape, and measure the thickness of ten points in total, taking the median value as the test result (rounded up to two significant figures). To prevent the resin from adhering to the measuring cap of the micrometer, the measuring cap of the micrometer may be lined with polyester film, and the thickness of the film shall be subtracted in calculation.
Foreword i
1 Scope
2 Normative references
3 General requirements for test
4 Width
5 Thickness
6 Volatile content
7 Resin content
8 Soluble resin content
9 Curability
10 Tensile strength and elongation at break before curing
11 Electrical strength
12 Arc resistance
13 Proof tracking index (PTI)
14 Tensile strength and elongation at break of annular specimen under normal condition
15 Tensile strength of annular specimen in hot state
16 Tensile strength of annular specimen after oil immersion treatment
17 Modulus of elasticity for tension of ring specimen under normal condition
18 Temperature index