1. What Is a 145kV Cable Joint?
UM 145kV cable joint connects two sections of high-voltage power cables in an underground transmission system. It provides a safe electrical connection and keeps the cable insulation continuous. Além disso, it protects the connection from moisture, dano mecânico, and other external factors.
Power utilities use 145kV cable joints in 110kV and 132kV transmission networks. These systems have a maximum voltage of 145kV. Portanto, each cable joint must match the electrical and mechanical needs of the cable system.
Hoje, many cities and industrial areas use underground power cables instead of overhead lines. Como resultado, the demand for reliable 145kV high-voltage cable joints continues to grow.
A high-quality cable joint helps maintain stable power transmission. Mais importante, it reduces the risk of insulation failure and unexpected power outages.

2. Main Types of 145kV Cable Joints
Different power projects require different cable joint designs. The choice mainly depends on cable construction, tamanho do condutor, insulation material, e condições de instalação.
2.1 145kV Pre-Molded Cable Joint
A 145kV pre-molded cable joint uses a factory-made rubber insulation body. Manufacturers produce this part under controlled conditions to ensure stable dimensions and insulation quality.
Durante a instalação, technicians place the pre-molded body over the prepared cable connection. The design provides insulation and controls the electrical field around the conductor connector.
Its main advantages include:
- Stable insulation quality.
- Good electrical performance.
- Compact product design.
- Faster installation.
- Reliable long-term operation.
Por estas razões, many underground power transmission projects use pre-molded joints for 110kV, 132kV, and 145kV XLPE cables.
2.2 145kV Plug-In Cable Joint
A 145kV plug-in cable joint uses a special plug-in connection structure. It creates a reliable electrical interface between compatible cable components or electrical equipment.
This design offers a clear installation process and helps reduce on-site assembly work. No entanto, engineers must check the interface size, estrutura de isolamento, and electrical rating before selecting the product.

2.3 145kV Wrapped Cable Joint
A wrapped cable joint uses special insulating tapes and stress-control materials. Technicians build the insulation structure around the cable connection during installation.
This design can meet certain special project needs. No entanto, modern 145kV XLPE cable systems often prefer factory-made pre-molded joint solutions because they offer better control over the main insulation structure.
2.4 145kV Transition Cable Joint
A 145kV transition cable joint connects two cables with different designs or insulation systems.
Por exemplo, it can connect:
- XLPE cable to oil-filled cable.
- XLPE cable to HPFF cable.
- Cabo condutor de cobre para cabo condutor de alumínio.
- Cabos com diferentes seções transversais de condutores.
- Cables with different insulation diameters.
Nestes casos, engineers must consider conductor connections, insulation compatibility, and electric field control. Portanto, manufacturers should review the complete cable specifications before production.
3. Main Structure of a 145kV XLPE Cable Joint
A typical 145kV XLPE cable joint contains several important parts. Cada parte tem uma função específica, and all parts work together to ensure safe operation.
Conector do condutor
The conductor connector joins the copper or aluminum conductors of two cable sections. Manufacturers normally use compression connectors or mechanical connectors.
A good connector provides low electrical resistance and sufficient mechanical strength. Além disso, its dimensions must match the conductor size.
Corpo de Isolamento Principal
The main insulation body provides electrical insulation between the conductor and the metallic screen.
Manufacturers commonly use silicone rubber or EPDM materials in pre-molded cable joints. These materials offer good insulation performance and suitable flexibility.
Sistema de controle de estresse
Stress control plays a key role in every 145kV high-voltage cable joint.
When technicians connect two cable sections, the electric field can become uneven around the conductor connector and insulation screen cutback. Portanto, the joint needs a suitable stress-control design.
This system helps distribute electrical stress and reduces the risk of partial discharge.
Semi-Conductive Screen
The semi-conductive screen creates a smooth electrical connection between the cable insulation and the joint insulation system.
It also helps control the electric field around the joint area.
Metallic Shielding
Metallic shielding restores electrical continuity across the cable joint. Manufacturers may use copper wires, copper mesh, or copper tape according to the cable design.
Além disso, the metallic screen provides a path for fault current and connects with the cable grounding system.
Outer Protective Layer
The outer protective layer protects the cable joint from moisture, corrosão, e danos mecânicos.
Para instalações subterrâneas, waterproof sealing plays an especially important role. Como resultado, the joint can maintain reliable performance in different soil and environmental conditions.

4. Technical Specifications of a 145kV Cable Joint
Before purchasing a 145kV cable joint, customers should confirm the cable voltage rating and construction details.
The following table shows typical application parameters:
| Parâmetro | Typical Specification |
|---|---|
| Tensão do cabo | 64/110kV or 76/132kV |
| Tensão máxima do sistema | 123kV or 145kV |
| Isolamento de cabos | XLPE |
| Material condutor | Cobre ou Alumínio |
| Seção transversal do condutor | 240–2500mm² |
| Tipo de junta | Pre-molded or customized |
| Material de isolamento | Borracha de silicone / EPDM |
| Instalação | Subterrâneo |
| Tela metálica | Copper wires or copper tape |
| Main standard | CEI 60840 |
These values describe common application ranges, not fixed specifications for every product. Actual requirements depend on the cable design and project documents.
Por exemplo, a 76/132kV XLPE cable system with a maximum voltage of 145kV needs a compatible 145kV cable joint.
Além disso, the manufacturer must check the cable insulation diameter, tamanho do condutor, screen structure, and outer sheath dimensions before production.

5. 145kV Cable Joint Installation Procedure
Correct installation directly affects the service life of a high-voltage cable joint. Even a well-designed product may fail if technicians do not follow the correct installation process.
Portanto, trained cable jointing technicians should complete the work according to the manufacturer’s installation manual.
Etapa 1: Prepare as extremidades do cabo
Primeiro, technicians measure and mark the cable according to the installation drawings. Então, they remove the outer sheath, tela metálica, semi-conductive layer, and insulation at the required positions.
They must keep the cable surface clean and avoid damaging the main insulation.
Etapa 2: Conecte os condutores
Próximo, technicians connect the two cable conductors with a compression or mechanical connector.
They should follow the specified installation dimensions and tightening requirements. Além disso, they must check the connector surface and connection quality.
Etapa 3: Instale o corpo de isolamento principal
After completing the conductor connection, technicians install the pre-molded insulation body.
They must place it in the correct position and keep the insulation interface clean. This step helps maintain the required electrical insulation.
Etapa 4: Instale os componentes de controle de tensão
Technicians install the stress-control parts according to the manufacturer’s drawings.
Correct positioning is very important because the stress-control system helps prevent high electrical stress around the cable screen cutback.

Etapa 5: Restaure a tela metálica
Próximo, technicians reconnect the metallic screen across the joint. They also connect the grounding components according to the cable system design.
This step ensures electrical continuity and provides a path for fault current.
Etapa 6: Complete Waterproofing
Technicians install the outer sealing and protective components. These parts prevent water from entering the joint and protect it from external damage.
Etapa 7: Realize testes elétricos
Finalmente, the project team carries out the required electrical tests and inspections. The team should check the test results before energizing the cable system.
6. Testing Standards for 145kV Cable Joints
Testing helps customers confirm the quality and electrical performance of a 145kV cable joint.
CEI 60840 covers extruded-insulation power cables and their accessories for rated voltages above 30kV up to 150kV. Portanto, this standard applies to 145kV cable systems.
Depending on the product design and project requirements, the testing program may include:
- Teste de descarga parcial.
- Teste de resistência à tensão CA.
- Lightning impulse voltage test.
- Heating cycle voltage test.
- Insulation resistance measurement.
- Conductor resistance test.
- Inspeção mecânica.
- Inspeção dimensional.
- Sealing and waterproof performance checks.
Além disso, customers should review the type test reports, registros de testes de rotina, and quality inspection documents.
Type tests verify the design, while routine tests help control production quality. Por esta razão, both types of records are important when selecting a 145kV cable joint supplier.

7. Applications of 145kV Cable Joints
145kV cable joints support many high-voltage power transmission projects.
Aplicações comuns incluem:
- Underground power transmission networks.
- High-voltage substations.
- Usinas de geração de energia.
- Sistemas de alimentação industrial.
- Solar power transmission projects.
- Offshore wind farm connections.
- Urban underground cable networks.
- Utility grid expansion projects.
For long-distance underground cable circuits, manufacturers cannot always supply one continuous cable length. Portanto, contractors need cable joints to connect different cable sections.
Além disso, reliable joints help utilities maintain continuous power transmission and reduce maintenance risks.
8. How to Choose a 145kV Cable Joint Manufacturer?
Choosing the right 145kV cable joint manufacturer is important for project quality and long-term safety.
Antes de fazer um pedido, customers should check the following points.
1. Voltage Compatibility
Primeiro, confirm that the cable joint matches the rated voltage and maximum system voltage. For a 145kV system, the joint must meet the electrical requirements of the complete cable circuit.
2. Cable Dimensions
Próximo, provide the conductor cross-section, diâmetro de isolamento, metallic screen details, and outer sheath dimensions. These details help the manufacturer select the correct joint design.
3. International Standards
Check whether the product meets IEC 60840 and the technical requirements in the project specification.
4. Product Testing
Ask the manufacturer for type test reports, registros de testes de rotina, and quality documents. These records help verify product performance.
5. Suporte de instalação
A professional supplier should provide installation manuals, technical guidance, and training support when required.
6. Project Experience
Finalmente, check the manufacturer’s experience with 110kV, 132kV, and 145kV cable accessories. Previous project experience can help customers assess the supplier’s technical capabilities.

9. 145kV Cable Joint Manufacturer and Supplier – DOS Group
DOS Group, through Dosense Cable, is a manufacturer and supplier of high-voltage cable accessories in China.
We provide cable joint and cable termination solutions for underground power transmission systems, including 110kV, 132kV, and 145kV applications.
Our product range includes:
- 145kV XLPE cable joints.
- 145kV pre-molded cable joints.
- High-voltage cable outdoor terminations.
- 145kV GIS cable terminations.
- Terminações de cabos internos.
- High-voltage cable accessories.
We can develop suitable solutions according to the customer’s cable specifications, including conductor material, área transversal, diâmetro de isolamento, metallic screen structure, and rated voltage.
Além disso, DOS Group supports technical documentation, product testing, installation manuals, and engineering communication for international power projects.
Whether you are a power utility, Contratante EPC, fabricante de cabos, or electrical equipment distributor, we can provide technical support and customized 145kV cable joint solutions.
Contact DOS Group today to request a 145kV cable joint quotation, technical datasheet, especificações do produto, and customized high-voltage cable accessory solutions.