1. What Is a 145kV Cable Joint?
А 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. Кроме того, it protects the connection from moisture, механическое повреждение, and other external factors.
Power utilities use 145kV cable joints in 110kV and 132kV transmission networks. These systems have a maximum voltage of 145kV. Поэтому, each cable joint must match the electrical and mechanical needs of the cable system.
Сегодня, many cities and industrial areas use underground power cables instead of overhead lines. Как результат, the demand for reliable 145kV high-voltage cable joints continues to grow.
A high-quality cable joint helps maintain stable power transmission. More importantly, 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, размер проводника, insulation material, и условия установки.
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.
Во время установки, 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.
По этим причинам, many underground power transmission projects use pre-molded joints for 110kV, 132кВ, 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. Однако, engineers must check the interface size, изоляционная конструкция, 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. Однако, 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.
Например, it can connect:
- XLPE cable to oil-filled cable.
- XLPE cable to HPFF cable.
- Copper conductor cable to aluminum conductor cable.
- Cables with different conductor cross-sections.
- Cables with different insulation diameters.
В этих случаях, engineers must consider conductor connections, insulation compatibility, and electric field control. Поэтому, 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. Each part has a specific function, and all parts work together to ensure safe operation.
Разъем проводника
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. Кроме того, its dimensions must match the conductor size.
Main Insulation Body
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.
Система контроля стресса
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. Поэтому, 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.
Более того, the metallic screen provides a path for fault current and connects with the cable grounding system.
Внешний защитный слой
The outer protective layer protects the cable joint from moisture, коррозия, и механические повреждения.
For underground installations, waterproof sealing plays an especially important role. Как результат, 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:
| Параметр | Typical Specification |
|---|---|
| Напряжение кабеля | 64/110kV or 76/132kV |
| Максимальное напряжение системы | 123kV or 145kV |
| Изоляция кабеля | СПЭ |
| Материал проводника | Медь или алюминий |
| Сечение проводника | 240–2500 мм² |
| Joint type | Pre-molded or customized |
| Изоляционный материал | Силиконовая резина / ЭПДМ |
| Монтаж | Метро |
| Металлический экран | Copper wires or copper tape |
| Main standard | МЭК 60840 |
These values describe common application ranges, not fixed specifications for every product. Actual requirements depend on the cable design and project documents.
Например, a 76/132kV XLPE cable system with a maximum voltage of 145kV needs a compatible 145kV cable joint.
Кроме того, the manufacturer must check the cable insulation diameter, размер проводника, 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.
Поэтому, trained cable jointing technicians should complete the work according to the manufacturer’s installation manual.
Шаг 1: Prepare the Cable Ends
Первый, technicians measure and mark the cable according to the installation drawings. Затем, they remove the outer sheath, металлический экран, semi-conductive layer, and insulation at the required positions.
They must keep the cable surface clean and avoid damaging the main insulation.
Шаг 2: Connect the Conductors
Следующий, technicians connect the two cable conductors with a compression or mechanical connector.
They should follow the specified installation dimensions and tightening requirements. Кроме того, they must check the connector surface and connection quality.
Шаг 3: Install the Main Insulation Body
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.
Шаг 4: Install the Stress Control Components
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.

Шаг 5: Restore the Metallic Screen
Следующий, 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.
Шаг 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.
Шаг 7: Perform Electrical Tests
Окончательно, 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.
МЭК 60840 covers extruded-insulation power cables and their accessories for rated voltages above 30kV up to 150kV. Поэтому, this standard applies to 145kV cable systems.
Depending on the product design and project requirements, the testing program may include:
- Тест частичного разряда.
- Испытание на устойчивость к переменному напряжению.
- Lightning impulse voltage test.
- Heating cycle voltage test.
- Insulation resistance measurement.
- Conductor resistance test.
- Механический осмотр.
- Проверка размеров.
- Sealing and waterproof performance checks.
Кроме того, customers should review the type test reports, routine test records, and quality inspection documents.
Type tests verify the design, while routine tests help control production quality. По этой причине, 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.
Общие приложения включают в себя:
- Underground power transmission networks.
- High-voltage substations.
- Электростанции.
- Промышленные системы питания.
- 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. Поэтому, contractors need cable joints to connect different cable sections.
Более того, 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.
Before placing an order, customers should check the following points.
1. Voltage Compatibility
Первый, 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
Следующий, provide the conductor cross-section, диаметр изоляции, 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, routine test records, and quality documents. These records help verify product performance.
5. Поддержка установки
A professional supplier should provide installation manuals, technical guidance, and training support when required.
6. Project Experience
Окончательно, check the manufacturer’s experience with 110kV, 132кВ, 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
Группа ДОС, 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, 132кВ, 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.
- Заделки кабелей внутри помещений.
- High-voltage cable accessories.
We can develop suitable solutions according to the customer’s cable specifications, including conductor material, площадь поперечного сечения, диаметр изоляции, metallic screen structure, and rated voltage.
Более того, DOS Group supports technical documentation, product testing, installation manuals, and engineering communication for international power projects.
Whether you are a power utility, EPC-подрядчик, производитель кабеля, 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, характеристики продукта, and customized high-voltage cable accessory solutions.