GB/T 29324-2024 Carbon fiber reinforced composite core for overhead electrical conductors
1 Scope
This document specifies the product models and representation methods, structure, technical requirements, inspection rules, packaging, marking, transportation and storage, acceptance and rejection criteria for carbon fiber reinforced composite core for overhead electrical conductors (hereinafter referred to as "composite core"). It also describes the corresponding test methods.
This document is applicable to the manufacture, test, and application of carbon fiber reinforced composite core for overhead electrical conductors.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 1463 Test methods for density and relative density of fiber reinforced plastics
GB/T 2572 Fiber-reinforced plastics composites - Determination for mean coefficient of linear expansion
GB/T 6995.1 Markings for electric wires and cables - Part 1: General requirements
GB/T 22315-2008 Metallic materials - Determination of modulus of elasticity and poissons ratio
GB/T 22567-2008 Electrical insulating materials - Methods of test for the determination of the glass transition temperature
JB/T 8137.2-2013 Delivery drums for wires and cables - Part 2: Wood delivery drums
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
composite material
new material formed by compositing two or more constituent materials through a specialized preparation process
Note: Composite materials retain the basic characteristics of the original constituent materials while possessing superior properties that cannot be achieved by the original single constituent material.
3.2
fiber reinforced composite core
conductor core made by compositing one or more types of continuous fibers
3.3
diameter
the average of two measurements taken in perpendicular directions on the same circular section
3.4
value f
the difference between the maximum and minimum diameters measured on the same circular section perpendicular to the axis
3.5
strength grade
classification made based on the tensile strength of composite core
3.6
temperature level
classification made based on the long-term allowable operating temperature of composite core
3.7
glass transition temperature
Tg
temperature at the midpoint of the range where glass transition occurs
Note: Glass transition is determined by observing the temperature at which specific electrical, mechanical, thermal or other physical properties change significantly. In addition, the observed temperature may vary significantly due to differences in the properties selected for observation and the technical details of the test (such as, heating rate, test frequency, etc.). Thus, the observed temperature t is considered only an approximation and valid for specific techniques and test conditions.
[Source: GB/T 22567-2008, 2.2]
3.8
dynamic mechanical analysis; DMA
a technique for measuring the relationship between a material's storage modulus and/or loss modulus and temperature, frequency, time, or a combination thereof, under vibrational load or deformation
[Source: GB/T 22567-2008, 2.7]
4 Product models and representation methods
4.1 Models
The model of a composite core consists of the category code, strength grade code, and temperature level code, and their corresponding names are shown in Table 1.
Foreword III
1 Scope
2 Normative references
3 Terms and definitions
4 Product models and representation methods
4.1 Models
4.2 Representation methods
5 Structure
6 Technical requirements
6.1 Appearance
6.2 Diameter deviation and value f
6.3 Stranding of composite core
6.4 Mass per unit length
6.5 Tensile strength
6.6 Long-term allowable operating temperature
6.7 Coefficient of linear expansion
6.8 Density
6.9 Winding
6.10 Radial pressure resistance performance
6.11 Glass transition temperature (DMA) Tg
6.12 Long-term heat resistance
6.13 Heat aging
6.14 Elastic modulus
6.15 Length and length deviation
6.16 Joint
7 Test methods
7.1 Appearance
7.2 Diameter
7.3 Mass per unit length
7.4 Tensile strength
7.5 Coefficient of linear expansion
7.6 Density
7.7 Winding
7.8 Radial pressure resistance
7.9 Glass transition temperature (DMA) Tg
7.10 Long-term heat resistance
7.11 Heat aging
7.12 Elastic modulus
8 Inspection rules
9 Packaging, marking, transportation and storage
9.1 Packaging
9.2 Marking
9.3 Transportation and storage
10 Acceptance and rejection
Annex A (Informative) Recommended structural parameters of composite cores
Annex B (Normative) Winding test
Figure 1 Structural diagram of TF composite core
Figure 2 Structural diagram of JTF composite core
Figure 3 Structural diagram of JBTF composite core
Figure B.1 Schematic diagram of the principle of the winding test machine
Table 1 Codes and names
Table 2 Diameter deviation and value f of composite core
Table 3 Stranding increment of JTF composite core
Table 4 Stranding increment of JBTF composite core
Table 5 Tensile strength of composite core
Table 6 Long-term allowable operating temperature of composite core
Table 7 Glass transition temperature (DMA) Tg of the composite core
Table 8 Elastic modulus of composite cores
Table 9 Radial pressure resistance test parameters of composite cores
Table 10 Long-term heat resistance test temperatures of composite cores
Table 11 Heat aging test temperatures of composite cores
Table 12 Inspection rules
Table A.1 Recommended structural parameters of TF composite core
Table A.2 Recommended structural parameters of JTF composite core
Table A.3 Recommended structural parameters of JBTF composite core
