JB/T 7831-1995 Indoor and outdoor cast-type terminals for power cables with rated voltage up to and including 8.7/10 kV
Some standard content:
Mechanical Industry Standard of the People's Republic of China
Indoor and outdoor cast-type terminals for power cables with rated voltages of 8.7/10kV and below
1 Subject content and scope of application
JB7831-1995
This standard specifies the product marking and code, technical requirements, test methods, inspection rules and signs, packaging, transportation and storage of indoor and outdoor cast-type terminals for power cables with rated voltages of 8.7/10kV and below. This standard applies to indoor and outdoor cast-type cable terminals for paper-insulated power cables and plastic-insulated power cables with rated voltages of U./U of 8.7/10kV and below. The use conditions shall comply with the provisions of Article 4.1 of GB11033.1. 2 Reference standards
GB2900.10
Electrical terminology Part 10 Wires and cables GB11033
GB14315
GB5589
GB9327
GB1034
GB1036
GB1041
GB1408
GB1409
GB1410
GB2406
GB2411||tt| |GB2568
GB2569
GB2571
GB6553
GB10582
JB7832
3 Terminology
Basic technical requirements for power cable accessories with rated voltage of 26/35kV and below Crimping type copper and aluminum terminals and connecting tubes for power cable conductors Test methods for cable accessories
Test methods for compression and mechanical connection joints of cable conductors High voltage test technology Part 2 Test procedure Open cup method
Petroleum Determination of flash point and fire point of products
Test method for water absorption of plastics
Determination method for linear expansion coefficient of plastics
Test method for compression of plastics
Test method for power frequency electrical strength of solid insulating materialsTest method for relative dielectric constant and dielectric loss factor of solid insulating materials at power frequency, audio frequency and high frequency (including meter wavelength)
Test method for volume resistivity and surface resistivity of solid insulating materialsTest method for combustion performance of plasticsOxygen index methodTest method for Shore hardness of plastics
Tensile test of resin castings Method
Compression test method for resin castings
Impact test method for resin castings
Test method for evaluating the tracking resistance and erosion resistance of electrical insulating materials used under severe environmental conditionsTest method for determining electrolytic corrosion caused by insulating materialsTest method for thermal conductivity of plastics
Straight-through cast joints for power cables with rated voltage of 8.7/10kV and below
Except the terms specified in this standard, other terms shall comply with the provisions of GB2900.10 and GB11033.1. 3.1 Thermosetting resin casting agent
Approved by the Ministry of Machinery Industry on November 24, 1995
Implemented on July 1, 1996
JB78311995
Thermosetting resin casting agent for cable accessories is composed of liquid thermosetting resin and compounding agent (curing agent, accelerator, etc.), which solidifies after addition polymerization, but does not decompose volatile components. 3.2 Casting terminal
Thermosetting resin casting agent is used to cast on-site at the end of the treated cable as an indoor and outdoor terminal for terminal body insulation.
Product marking and code
4.1 Code
4.1.1 According to series
Indoor terminal series
Outdoor terminal series
4.1.2 According to material and process characteristics
Epoxy resin casting type
Polyurethane casting type
4.1.3 According to the type of supporting cables
Paper insulated power cable
Plastic insulated power cable||tt ||4.1.4 According to the order of design
First design
Second design
(and so on)
4.1.5 According to voltage level
1.8/3kV and below...
3.6/6, 6/6, 6/10kV..
8.7/10kV.
4.1.6 According to the number of cable cores
4.2 Product representation method||tt ||4.2.1 The composition and arrangement order of product models are as follows: 4.2.2 Example
JB7831-1995
Cable core number code
Voltage level code
Design sequence code
Matching cable variety code
Material and process characteristic code
Series code
JB7831-1995
8.7/10kV3 core paper insulated power The second design of outdoor epoxy resin special terminal of cable is expressed as: WHZ--2—33JB7831—1995;
The first design of indoor polyurethane cast terminal of 6/10kV 3-core plastic insulated power cable is expressed as: NA-1—23JB7831-1995;
5 Technical requirements
Indoor and outdoor cast terminals shall comply with the following provisions in addition to the requirements of GB11033 standard. 5.1 The casting materials used for indoor and outdoor cast terminals shall comply with the requirements of Appendix A and Appendix B of this standard. 5.2 The conductor connection fittings shall comply with the corresponding provisions in GB14315, and the DC resistance of the copper-aluminum transition terminal shall not be greater than 1.2 times the DC resistance of the aluminum conductor of the same length and cross-section. 5.3 The insulation material of outdoor terminal should have the performance of resistance to leakage trace and electric corrosion. 5.4 Grounding wire
The grounding wire of the terminal should be tinned copper wire. Its cross section is recommended to be selected according to the provisions of Table 1, or it can be selected according to the principle of consistency with the cross-sectional area of the cable metal shielding layer.
Main wire core cross section of electrical insulation
35 and below
50~120
150~400
5.5 Electrical performance
50 and below
70~150
185400
Grounding wire cross section
According to the installation process instructions provided by the manufacturer, install the various materials and components of the provided cable terminal on the cable end of the corresponding specification with reliable performance, and then conduct electrical performance test. The test items and requirements should comply with the provisions of Table 2a, Table 2b or Table 3a, Table 3b. 6 Test methods
The requirements specified in Article 5.1 shall be tested in accordance with the test methods specified in Appendix A. 6.2
The requirements specified in Article 5.2 shall be tested in accordance with the test methods specified in GB9327.2. The requirements specified in Article 5.3 shall be tested in accordance with the test methods specified in GB6553. 6.3
The requirements specified in Article 5.5 shall be tested in accordance with the test series and test methods specified in Table 28, Table 2b or Table 3a, Table 3b. 6.41
Inspection rules
The product shall be inspected and qualified by the technical inspection department of the manufacturer before it can be shipped out of the factory. The shipped products shall be accompanied by a product quality inspection certificate. 7.1 Type test
The product shall be type tested in accordance with the requirements of Article 5.15.3 and Table 2a or Table 2b of Article 5.5. The short-circuit test series shall be determined by the supply and demand parties through negotiation whether to conduct the test. When the supporting cable is a plastic insulated cable, Table 2a shall be used; when it is a paper insulated cable, Table 2b shall be used. The number of samples and the evaluation method of the test results shall be in accordance with the corresponding provisions of the three types of terminals in GB11033. 7.2 Sampling test
7.2.1 During normal production, a sampling test shall be carried out once every 35 years. It shall also be carried out when the user makes a request and both parties agree. 7.2.2 The product shall be sampled and tested in accordance with the requirements of Table 3a or Table 3b in Articles 5.2 and 5.5. When the supporting cable is a plastic insulated cable, Table 3a shall be used; when it is a paper insulated cable, Table 3b shall be used. The number of samples and the evaluation method of the test results shall be in accordance with the corresponding provisions of the three types of terminals in GB11033.
8 Marking, packaging, transportation, storage
JB7831-1995
8.1 The casting materials and main components used in the terminal should be marked with brand, name, factory name, and production date, and attached with a certificate of conformity or acceptance mark: materials with a storage period must indicate the production date and storage period. 8.2 Various materials used in the terminal should be sealed and packaged separately. Each set of cast-type terminals should be packaged in a special packaging box, which should be accompanied by a material list, product certificate of conformity and installation process instructions. 8.3
The packaging box should indicate:
Manufacturer name;
Product model, name, product standard number; rated voltage;
Conductor material, carrier surface and number of cores:
Factory date.
8.4 Products should be protected from heavy pressure and violent collision during transportation. Products should be stored away from heat sources, with fire prevention measures, dry and ventilated. The storage period should not exceed the storage date of the corresponding supporting materials and accessories. 8.5
Test items
Rated voltage test
a. Dry state 1min
b. Wet state 1min
Partial discharge test
Constant voltage load cycle
Test 3 cycles
Partial discharge test
Constant voltage load cycle
a.123 cycles
b.114 cycles
Load cycle test
(without voltage) 9 weeks
Short circuit test
Short circuit thermal stability
Short circuit dynamic stability
Salt spray test 1000h
Tidal flooding test 100h
Impulse voltage test
1. 2/50 μ8±10
DC voltage test
Negative polarity 15min
Power frequency voltage test
Partial discharge test
Appearance inspection
6/6, 6/10
JB 78311995
Test method
(The conductor is heated by electric current for 5h and cooled for 3h. When heating, the maximum temperature of the conductor is the allowable working temperature of the cable plus 5℃)
(The conductor is heated by electric current for 5h and cooled for 3h. When heating, the maximum temperature of the conductor is the allowable working temperature of the cable plus 5℃)
(The conductor is heated by electric current for 5h and cooled for 3h. When heating, the maximum temperature of the conductor is the allowable working temperature of the cable plus 5℃. The entire cable terminal sample should be immersed in water.)||tt ||(Each sample is short-circuited twice, and the current value shall
comply with the provisions of Table 1 of GB11033.1)
(Each sample is short-circuited once, and the current is 63
(All cable terminal samples need to be visually inspected after all tests have passed)
GB11033.1
Article 5.1
Under consideration
GB311.3 and
GB11033.1
Article 5.3
GB311.3 and
CB11033.1
Article 5.2
CB11033.1
Article 5.1
Test result evaluation
No flashover, no breakdown
Under the specified extinguishing voltage,
The effective quantity of XLPE cable is not large
For 20PC
PVC cable is not more than 40PC
Assessed by subsequent tests
Under the specified extinguishing voltage,wwW.bzxz.Net
The discharge quantity of XLPE cable is not large
For 20PC
PVC cable Not more than 40PC
Assessed by subsequent tests
Assessed by subsequent tests
Assessed by subsequent tests
According to GB5589.5
According to GB5589.6
No breakdown, positive and negative polarity are allowed to flash over once, but it is not included in the total
test times
No flashover, no breakdown
No flashover, no breakdown
Under the specified extinguishing voltage, the discharge amount of XLPE cable is not more than 20 PC
PVC cable is not more than 40PC
No cracks, deformation, leakage, electric
Indoor terminal Outdoor terminal
Libai Baiguang
Power frequency voltage test
a. Dry state 1min
b. Wet state 1min
Constant voltage load cycle test
a.126 cycles
h.117 cycles
Load cycle test
(without voltage) 9 cycles||tt| |Short circuit test
Short circuit thermal stability
Short circuit dynamic stability
Salt test 1000h
Humidity test 100h
Impulse voltage test
1.2/50μs±10 times
DC voltage test
Negative polarity 15min
Power frequency voltage test
Appearance inspection
0.6/13.6/6
6/6, 6/10
JB 7831—1995 (The conductor is heated by electric current for 5 hours and cooled for 3 hours. The maximum temperature of the conductor during heating is the allowable working temperature of the cable plus 5°C) (The conductor is heated by electric current for 5 hours and cooled for 3 hours. The maximum temperature of the conductor during heating is the allowable working temperature of the cable plus 5°C. The entire cable terminal sample should be immersed in water. )
(Each sample is short-circuited twice, and the current value
should comply with the provisions of Table 1 of GB11033.1
(Each sample is short-circuited once, and the current is
(All cable terminal samples shall be inspected for appearance after all tests
passed)
Test method
GB11033.1
Article 5.1
Under consideration
GB311.3 and
GB11033.1 Article
GB31 1.3 and GB11033.1, No. 1, GB11033.1, No. 1, Test results assessment: No flashover, no breakdown; Assessed by subsequent tests; Assessed by subsequent tests; Assessed by subsequent tests; Assessed by subsequent tests; According to GB5589.5; According to GB5589.6; No breakdown, positive and negative polarities are allowed to be internally connected once each, but not included in the total number of tests. Internal
No flashover, no breakdown
No flashover, no breakdown
No crack, deformation, leakage
Insulating agent
Indoor terminal
Outdoor terminal
Test items
Power voltage test
a. Dry state 1min
b. Wet state 1min
Partial discharge test
Load cycle test
(no voltage) 3 cycles
Partial discharge test
Impulse voltage test
1.2/50us±19 times
DC voltage test
Negative polarity 15min
Power frequency voltage test
Test items
Power frequency voltage test
a.Dry state 1min
b.Wet state 1min
Impact voltage test
1.2/50μs±10 times
DC voltage test
Negative polarity 15min
Power frequency voltage test
JB 7831-1995
6/6, 6/10
(the conductor is heated by electric current for 5 hours and cooled for 3 hours. The maximum temperature of the conductor during heating is the allowable working temperature of the cable plus 5°C)
6/6, 6/10
GB11033.1
Article 5.1
GB 5589.3
GB311.3 and
GB11033.1
Article 5.3
GB311.3 and
GB11033.1
Article 5.2
GB11033.1
Article 5.1
GB11033.1
Article 5.1
GB311.3 and
GB11033.1
Article 5.3
GB311.3 and
GB11033.1
Article 5.2
GB11033.1
Article 5.1
Test result evaluation
No flashover, no breakdown
Discharge at the specified extinguishing voltage
XLPE cable is not more than 20PC
PVC cable is not more than 40PC
Evaluated by subsequent tests
Discharge at the specified extinguishing voltage
XLPE cable is not more than 20PC
PVC cable is not more than 40PC
No breakdown, positive and negative polarity are allowed to flash over once, but it is not included in the total
test number
No flashover, no breakdown
No flashover, no breakdown
Test result evaluation
No flashover, no breakdown Wear
No breakdown, positive and negative polarity are allowed to flash over once each, but it is not included in the total
test number
No flashover, no breakdown
No internal flashover, no breakdown
Test series
Indoor terminal Outdoor terminal
Test series
Indoor terminal Outdoor terminal
JB7831-1995
Appendix A
General technical requirements for thermosetting resin castings for power cable accessories
(supplement)
A1 The requirements specified in the appendix to this standard apply to thermosetting room temperature curing resin castings with epoxy resin and polyurethane resin as basic materials used for power cable parts.
A2 Casting agent manufacturers should conduct tests according to the items (1 to 19) specified in Appendix B. Under normal production conditions, every two years, they should conduct sampling tests according to items 2, 3, 18, 12 (flame retardant); 15, 16, 18 (used as outdoor terminal external insulation); 19 (used for paper insulated cables) in Appendix B, and provide test reports according to supply requirements. Sampling tests can also be negotiated when users require it. Accessory manufacturers can also use the requirements specified in Appendix B as the basis for acceptance of casting agents.
A3 Each component of the casting agent should be packaged separately in a sealed container, and the packaging method should be convenient for on-site operation. A4
The following instructions should be attached to the packaging container:
Type of base material of the casting agent;
Brief instructions on the mixing and pouring process of the casting agent (including the casting time limit); Operation safety precautions;
Minimum waiting time after casting until acceptance test or commissioning: Storage conditions and storage period;
Production date;
Manufacturer name and registered trademark;
Net weight of casting material:
Standards that the casting performance meets.
Note: If the writing space on the packaging container is limited, the above items bc and d can be explained separately. A5
The manufacturer must also provide the following information:
The maximum reaction temperature at an ambient temperature of 35°C; The volume expansion coefficient of the solidified casting in the temperature range of 26°C to 50°C; The thermal conductivity of the solidified casting.
Flash point (in an open crucible)
Material not participating in the reaction
Material participating in the reaction
Pouring time limit (per package quantity)
JB7831-1995
Appendix B
Main performance requirements of thermosetting resin casting agent for power cable accessories
(Supplement)
Not less than
Not less than
Not less than
At ambient temperature of 5℃, 23℃, 35℃
Maximum reaction temperature|| tt||Physical structure
Impact strength
Compressive strength
Compression test
30% compression stress
Residual deformation after unloading for 24 hours
Hardness (Shore D)
Tensile strength
Elongation at break
Thermal conductivity
Combustion characteristicsOxygen index
Water absorption
23℃ cold water immersion for 24 hours
50℃ hot water immersion for 42 days
Coefficient of thermal expansion
(from 20℃ to 50℃）
Working jaw compressive strength 23℃1min
Dielectric constant (50Hz) 23℃
Volume resistivity
After 24h of immersion in water at 23℃
Anti-leakage trace performance\
Oil resistance
80℃ viscous immersion in cable oil for 168h
Weight change rate
Note: 1)
Not more than
Not less than
Not less than
Not less than
Not more than
Not less than
Not less than
Not less than
Not less than
Not less than
Not greater than
Not greater than
Not greater than
Not less than
Not less than
Not less than
Not less than
Not greater than
Nmm/mm
Wmtk-1
This requirement only applies to external insulation castings used for medium voltage outdoor terminals; This requirement only applies to castings used for paper insulated ropes. 2)
Polyurethane
Epoxy resin
The specimen should be cut evenly along the middle and axis, without visible bubbles. Individual bubbles on the surface can be ignored. 10
1×10-4
Test method
Appendix C of this standard
Appendix C of this standard
Appendix C of this standard
GB2571
GB2569
GB1041
GB2411
GB2568
GB2568
GB2406
GB1034
GB 1036
GB1408
GB1409
GB1410
GB6553
Appendix C of this standard
C1 Test method for casting time limit
JB7831-1995
Appendix C
Test method for main properties of thermosetting resin casting agent for power cable accessories
(Supplement)
The casting time limit refers to the period from the time when the components of the casting agent are mixed together until the casting agent can just flow smoothly and continuously from a glass rod without visible gel component, that is, the time allowed for casting. C1.1 Test equipment
A glass rod with a diameter of about 8mm and a length of about 250mm; a.
A container for storing the tested casting agent;
A container with an insulating layer for storing the container in item b; a naturally ventilated electric heating oven;
A 0～50℃ thermometer;
A timer.
C1.2 Test operation
C1.2.1 Place the tested casting agent (including resin, curing agent and other compounding agents) and the objects in items a, b and c in item C1.1 in the electric heating oven, make them reach the specified temperature, and keep it for 1 hour. C1.2.2 According to the instruction manual, inject the various components of the casting agent into the container in item b of item C1.1 (the container is placed in the heat-insulating container in item c), mix them thoroughly and evenly with a glass rod under constant temperature, and record the time from the beginning of mixing. C1.2.3 Insert the glass rod from the middle of the mixture to 1/2 of its depth at appropriate intervals, then pull it out vertically to about 20 cm from its surface, and observe the casting agent flowing down from the glass rod. If gel particles appear in the flowing material, or it can only be picked off instead of flowing down from the glass rod continuously, it means that the use time has been exceeded. Record the time when this situation occurs and round it off to minutes, which is the casting time limit for the package.
C2 Test method for maximum reaction temperature and physical structure Test according to the method specified in Article C2 of Appendix C of JB7832. C3 Test method for oil resistance
C3.1 Test equipment and materials
3 beakers of 300ml;
1 electric constant temperature water bath:
Sky platform sensitivity 0.1g;
300ml viscous impregnated cable oil;
3 specimens with a diameter of @50mm and a thickness of 2mm. e.
C3.2 Test operation
Pour 100ml of viscous cable oil into three beakers respectively, and then put them into an 80℃ electric constant temperature water bath. After 5 minutes, put the three samples into the three beakers respectively (the samples should be completely immersed in the cable oil), and start timing. After 168 hours, take out the samples, and use filter paper to repeatedly absorb the oil on the surface of the samples until there is no obvious oil mark on the filter paper, and then weigh the sample. The oil absorption rate is calculated according to formula (C1): w=G=C×100%..
Weight of sample before oil immersion, g;
Where: G,
G.The weight of the sample after oil immersion, g;
W-oil absorption rate, %.
Take the arithmetic mean of 3 samples.
Additional instructions:
JB7831
This standard was proposed and coordinated by the Shanghai Cable Research Institute of the Ministry of Machinery Industry, and this standard was drafted by the Shanghai Cable Research Institute of the Ministry of Machinery Industry. The main drafter of this standard is Ge Guangming.
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