The Kerun oil-immersed power transformer is designed through advanced electromagnetic simulation and energy efficiency optimization to achieve high operational efficiency and low total losses. Its total losses consist of two main components—no-load loss and load loss—both fully compliant with or superior to the limits defined in GB 1094 and IEC 60076 international standards.

No-load Loss:

• Primarily resulting from core hysteresis and eddy current losses, minimized through the use of high-permeability grain-oriented silicon steel, precision step-lap stacking, and stress-relief annealing.
• For standard designs, no-load loss typically ranges from 2% to 0.35% of the rated capacity, while high-efficiency models can achieve values below 0.15%.
• The no-load current is generally maintained within 3% to 0.5%of the rated current, significantly reducing reactive power losses.

Load Loss:

• Mainly caused by winding resistance and stray flux losses. By utilizing low-resistivity oxygen-free copper conductors, optimized winding configurations, and efficient oil duct cooling, Kerun effectively minimizes I²R and additional stray losses.
• Typical load loss values are 8% to 1.2% of the rated capacity, and can be reduced to as low as 0.7%in energy-efficient models.
• Under rated load conditions, the average winding temperature rise remains within ≤65K, and top oil rise ≤60K, ensuring stable long-term operation.

Overall Efficiency:

• The overall transformer efficiency typically ranges between 5% and 99.2%, depending on capacity and load ratio.
• For large-capacity high-efficiency designs, operational efficiency can exceed 3%at rated load.
• Through the integration of low-loss materials and optimized electromagnetic design, Kerun transformers significantly reduce annual energy consumption and operational costs, making them ideal for heavy-duty, continuous-service applications.

The Kerun oil-immersed power transformer is equipped with various cooling systems—ONAN (Oil Natural Air Natural), ONAF (Oil Natural Air Forced), OFAF (Oil Forced Air Forced), and OFWF (Oil Forced Water Forced)—selected according to the unit’s capacity, operational environment, and site conditions. Each configuration is designed to ensure safe, stable, and efficient thermal performance across diverse climates, load profiles, and installation types.

Cooling System Principles and Design Features

• ONANcooling relies on natural oil convection, suitable for small and medium-capacity transformers, featuring a simple structure, high reliability, and minimal maintenance requirements.
• ONAF/OFAFsystems incorporate fans and oil pumps to enhance oil and air circulation, improving heat dissipation efficiency by 30%–50%, ideal for medium to large transformers and continuous heavy-load operation.
• OFWFsystems use oil–water heat exchangers for environments with limited ventilation or extreme heat, such as underground substations, offshore platforms, or industrial high-temperature zones.
• All systems are equipped with automatic temperature control units, activating fans or pumps at preset temperature thresholds to achieve staged cooling and optimized energy consumption.

Structural Optimization and Intelligent Monitoring

Kerun applies computational fluid dynamics (CFD) to optimize oil flow and radiator design. Radial oil ducts, longitudinal guide channels, and corrugated tanks ensure uniform oil distribution and eliminate local hot spots. The radiators feature high-conductivity steel fins for efficient heat transfer and low noise.
Optional smart thermal monitoring modules continuously measure oil and winding temperatures, as well as fan and pump status. Through PLC or SCADA integration, real-time data enables remote supervision, fault diagnosis, and predictive maintenance.

Performance Across Climate Conditions

• High-temperature regions (e.g., Middle East, Southeast Asia):OFAF or OFWF systems combined with high-temperature-resistant seals and advanced insulating oil prevent overheating and insulation aging.
• Cold regions (e.g., Siberia, plateaus):Low-pour-point mineral or synthetic ester oils ensure smooth oil flow and startup reliability at sub-zero temperatures.
• Humid or coastal environments:Multi-layer anti-corrosion coatings (epoxy + polyurethane), sealed breathers, and moisture-absorbing filters protect against corrosion and oil degradation.
• High-altitude areas (>2000 m):Cooling capacity is increased, and oil circulation is adjusted to compensate for reduced air density and heat transfer efficiency.

Operation, Maintenance, and Reliability

All cooling equipment undergoes long-duration performance tests. Fans and pumps feature low-noise axial designs. Automatic start/stop control, over-temperature alarms, and interlock protections ensure stable performance even under extreme climatic or loading conditions.
Furthermore, Kerun provides lifecycle energy management and predictive maintenance systems, helping users minimize energy losses and maintenance costs throughout the transformer’s operational life.

Under standard operating conditions, the Kerun oil-immersed power transformer has a designed service life of 25 to 35 years, and with proper load management and regular maintenance, its actual operational lifespan can exceed 40 years. The transformer’s longevity primarily depends on its insulation system, thermal design, operating conditions, and maintenance quality.

Key Life-Determining Factors and Design Assurance

1. Insulation Life:The insulation system employs high thermal class electrical paper and oil-paper composite materials, processed through vacuum drying and oil impregnation. Its thermal aging life meets IEC 60076-7 standards, maintaining stable dielectric strength at continuous operating temperatures below 105°C.
2. Thermal Management:Optimized cooling design ensures uniform temperature distribution within the windings and oil, minimizing local hot spots and slowing down insulation degradation.
3. Electrical and Mechanical Strength:Windings, clamps, and core structures are verified through electromechanical simulations and short-circuit withstand tests, preventing permanent deformation under grid disturbances or fault conditions.
4. Oil Stability:High-purity mineral or synthetic ester insulation oils with excellent oxidation resistance and anti-aging performance are used. Regular oil testing and purification extend overall service life.
5. Sealing and Anti-Corrosion:Multi-layer anti-corrosion coatings and robust sealing systems prevent ingress of moisture, dust, and corrosive gases, ensuring long-term reliability even in harsh environments.

Operating Conditions and Lifetime Variations

• Under standard load (≤ rated capacity)and ambient temperature between -25°C and +40°C, the transformer achieves its full design life.
• In high-temperature, humid, or heavy-load environments, forced cooling and continuous oil monitoring effectively minimize thermal aging.
• When operating under light load with proper maintenance, the transformer’s lifespan can be significantly extended.

Maintenance and Life Extension Strategy

Kerun recommends establishing a comprehensive maintenance schedule, including periodic testing of oil dielectric strength, moisture content, partial discharge level, and temperature rise monitoring. Combined with intelligent condition monitoring and lifetime assessment, such practices can reduce total lifecycle costs by 10–20% while ensuring high operational reliability and safe long-term performance.

Yes. The Kerun oil-immersed power transformer can be fully customized to meet specific operational, environmental, and digital requirements. In addition to electrical and structural modifications, it supports advanced remote monitoring, AI-based predictive maintenance, and enhanced safety control systems, ensuring reliable performance in various industries and climates.

1. Remote Monitoring Functionality

Kerun’s remote monitoring system continuously collects and transmits key operational data, allowing operators to supervise transformer status from any location.

Main Monitoring Parameters:

• Temperature monitoring:Real-time measurement of oil temperature, top-oil temperature, and winding temperature, with automatic fan and pump control.
• Electrical data:Continuous monitoring of three-phase voltage, current, load rate, power factor, and energy output.
• Oil and gas analysis:Oil level tracking and dissolved gas analysis (DGA) detect early signs of insulation degradation or discharge.
• Partial discharge (PD):Online PD monitoring using acoustic and electrical detection for real-time insulation assessment.
• Cooling equipment status:Real-time feedback on fan and pump operation ensures thermal stability and reliability.

Communication & Integration:

• Supports RS485, Modbus, IEC 61850, DNP3.0, and CAN-buscommunication protocols.
• Compatible with SCADA, IoT, and EMS platforms, enabling cloud-based monitoring and control.
• Offers data logging, trend analytics, alarm linkage, and remote maintenance access, available via LAN or cellular network.

2. Other Customization Options

In addition to monitoring, Kerun provides multiple customization options tailored to installation environments and operational needs:

Environmental Adaptations:

• High-temperature / cold-climate versions:Use OFAF or OFWF cooling systems with temperature-resistant or low-pour-point insulating oils.
• Explosion-proof / corrosion-resistant versions:Designed with sealed and coated structures suitable for chemical, offshore, or coastal applications.
• High-altitude versions:Enhanced insulation clearances and upgraded cooling design for operation above 2000 m altitude.

Electrical & Mechanical Configurations:

• Voltage range:10 kV–220 kV, available in single-, dual-, or triple-winding structures.
• Capacity range:800 kVA–100 MVA, configurable based on system load.
• Insulation class:Options for A, F, or H class insulation systems for extended thermal endurance.
• Protection level:IP33–IP55 enclosures for outdoor or high-contamination environments.

3. Intelligent Maintenance & AI Integration

The Kerun Smart TMS (Transformer Monitoring System) incorporates artificial intelligence for predictive maintenance and operational optimization:

• Fault prediction:Detects abnormal temperature trends, oil degradation, or partial discharge patterns and issues maintenance alerts.
• Life assessment:Estimates remaining service life based on temperature, load, and oil condition.
• Optimization support:Provides data-driven recommendations for cooling and energy efficiency improvements.
• Remote diagnostics:Enables remote health evaluation via mobile or cloud platforms for unattended smart operation.

4. Enhanced Safety and Control

To ensure operational and data security, the system employs multi-layer protection measures, including:

• Encrypted communicationusing SSL/TLS and user authentication.
• Fire and explosion protectioncomplying with IEC 60079, with dual safeguards for oil pressure and temperature rise.
• Access control and traceabilityof all maintenance operations.
• Emergency interlock protectionfor automatic power cutoff in case of over-temperature, short-circuit, or oil leakage events.

In summary, Kerun’s custom-built transformers integrate cutting-edge monitoring, control, and AI technologies to deliver high-efficiency, safe, and intelligent energy transformation solutions, adaptable to diverse operating environments worldwide.

Yes. Kerun’s oil-immersed power transformers are designed and manufactured in full compliance with international, national, and environmental safety standards, ensuring reliability, compatibility, and safety in diverse operating environments worldwide.

1. International Design and Manufacturing Standards

Kerun’s products comply with the following major standards:

• IEC Standards:

• IEC 60076 – Power Transformers
• IEC 60296 – Insulating Oils
• IEC 60085 – Thermal Insulation Classes
• IEC 60068 – Environmental Testing
• IEC 60137 – Bushings
  • IEEE/ANSI Standards (USA):
• IEEE C57 series – Design, Testing, and Loading Guides
• ANSI C57.12 – Design and Performance Requirements
  • BS Standards (UK):
• BS 1717 and related transformer specifications by the British Standards Institution (BSI)
• Commonly used in the UK and Commonwealth countries
  • IS Standards (India):
• IS 2026 – Power Transformer Design and Testing
• IS 1180 – Installation and Operation Guide by the Bureau of Indian Standards (BIS)
  • JIS Standards (Japan):
• JIS C 4210 – Transformer performance and safety specifications
  • AS Standards (Australia):
• AS 60076 – Aligned with IEC and IEEE standards

2. National and Industry Standards

In China, Kerun’s transformers fully comply with:

• GB/T 1094 – Power Transformer Standards
• GB/T 6451 – Technical Requirements for Oil-Immersed Transformers
• GB/T 7595 – Maintenance Guide for Transformer Oil
• DL/T and NB/T standards – Specific to the State Grid and Southern Grid utilities

For export projects, Kerun adapts to the relevant national or regional codes, ensuring conformity with local grid requirements and technical regulations.

3. Environmental and Safety Certifications

Beyond performance standards, Kerun also meets global environmental and safety certifications:

• RoHS Compliance:Restriction of Hazardous Substances – lead-, mercury-, and cadmium-free materials;
• ISO 9001:Certified quality management system ensuring consistent design, production, and testing;
• ISO 14001:Environmental management certification minimizing waste, emissions, and impact;
• UL / CSA:International safety certification recognized in North America;
• ISO 45001:Occupational health and safety management certification for safe manufacturing environments.

4. Certification and Conformity Declarations

• Third-party witness testing and certifications available (SGS, KEMA, CE, etc.);
• Export products comply with CE (EU), UKCA (UK), GCC (Middle East), and other international conformity requirements;
• Each transformer is delivered with full traceability records, test reports, and conformity certificatesfor project-level acceptance.

Conclusion

Kerun’s transformers are engineered and certified to meet IEC, IEEE, GB, ANSI, BS, IS, JIS, and AS standards, supported by complete environmental, quality, and safety certifications (ISO, RoHS, UL).
This ensures global interoperability, long-term reliability, and compliance with international and national regulations across all application environments.

The production and delivery schedule of a transformer depends on its model type, design complexity, capacity, and customization level. Kerun follows a strict production planning and quality management system to ensure on-time delivery while maintaining reliability and performance.

1. Standard Production Schedule

The standard lead time is calculated from the date the contract is signed, not from the order confirmation.
For standard oil-immersed power transformers, the average production and delivery time is 10–14 weeks.
This period covers design review, material procurement, core stacking, winding fabrication, assembly, vacuum drying, oil filling, routine testing, and final inspection.

2. Schedule for Special Products and Accessories

The lead time may be extended when the transformer includes:

• Non-standard designs or special voltage ratios (e.g., multi-winding structures);
• Intelligent monitoring systems, special cooling, explosion-proof, or anti-corrosion features;
• Imported or specialized materials such as high-permeability steel, advanced insulation, or bio-based oils;
• Third-party certification (CE, KEMA, SGS) or export packaging requirements;
• Customized accessories such as tap changers, bushings, or sensors.

In such cases, the production period is typically extended by 2–4 weeks.
For large-capacity, export, or highly customized transformers, the lead time may be significantly longer—up to or exceeding 18–20 weeks.

3. Key Factors Affecting Delivery Time

• Technical confirmation period, including approval of drawings and specifications;
• Material procurement timeline, particularly for imported or special materials;
• Testing and certification, especially for type tests or third-party inspections;
• Customer coordination, including contract execution, payment milestones, and logistics arrangements.

4. Expedited and Flexible Delivery Options

Kerun can provide expedited production services for urgent or time-critical projects.

• Standard models can be delivered within 8–10 weeksdepending on factory capacity;
• Expedited production maintains all testing and quality standards through optimized parallel scheduling;
• Partial shipment and on-site technical support are available for large-scale or strategic projects.

Conclusion

• Standard delivery:10–14 weeks after contract signing
• Special/customized products:12–18 weeks
• Complex or certified projects:may take longer (over 20 weeks)
• Expedited production:as fast as 8–10 weeks

Kerun ensures efficient, reliable, and traceable delivery through digital scheduling, lean manufacturing, and rigorous quality control — meeting customer deadlines with precision and consistency.

Yes. Kerun offers fully integrated power system solutions, leveraging our complete industrial chain covering transformers, switchgear, and electrical components.
In addition to oil-immersed power transformers, we independently design and manufacture:

• High- and low-voltage switchgear and distribution panels;
• Compact and modular substationsfor urban grids, renewable energy, and industrial applications;
• Smart monitoring and control systemswith remote supervision and fault diagnostics;
• EPC turnkey services, including design, manufacturing, installation, commissioning, and maintenance.

With in-house capabilities in both equipment manufacturing and system engineering, Kerun delivers seamless integration, consistent quality, and optimized performance across all components.
This ensures higher efficiency, lower operating costs, and reliable long-term operation for customers’ power distribution networks.

Yes. Kerun fully supports third-party inspection and client witness testing as part of our transparent and traceable quality assurance process.
We operate a comprehensive in-house testing center equipped with advanced facilities to perform all routine, type, and special tests in accordance with IEC, GB, and IEEE standards. These include:

• Routine tests, type tests, and special performance verification;
• Oil sample analysis, withstand voltage tests, partial discharge, noise, and temperature rise tests;
• On-site witness inspection by clients, consultants, or third-party agenciessuch as SGS, KEMA, CE, and UL.

Many of our customers regularly visit our factory for on-site inspections and witness testing. Kerun provides full coordination and hospitality, including plant tours, live test data observation, and post-test result reviews.

With an open testing environment and rigorous quality traceability system, Kerun ensures every transformer delivered meets or exceeds all contractual and international standards.

Yes. Kerun designs transformers with environment-specific adaptations to ensure reliable and safe operation under extreme climatic and geographical conditions such as high temperature, low temperature, and high altitude.

Our engineering team tailors each design based on the site’s ambient temperature, humidity, altitude, and air density, optimizing the following aspects:

• High-Temperature Regions(e.g., desert or tropical climates)

• Enhanced radiator and oil circulation system for improved cooling;
• Use of high-temperature-grade insulation and conductor enamel;
• Capacity and temperature-rise adjustments according to ambient temperature to prevent overheating.
  • Low-Temperature Regions(e.g., high-latitude or cold climates)
• Low-viscosity or bio-based transformer oils suitable for cold starts;
• Anti-condensation and anti-brittle treatment for tanks and accessories;
• Optional oil heaters or automatic temperature control systems for stable operation in sub-zero conditions.
  • High-Altitude Regions(typically above 1000 m)
• Adjusted insulation clearances and cooling design for reduced air density;
• Reinforced insulation and recalculated creepage distances to prevent partial discharge;
• Special thermal and dielectric design for installations above 3000 m.

Additionally, Kerun transformers can be equipped with anti-corrosion, moisture-proof, and dust-proof coatings, and customized IP55 or higher protection levels for coastal or industrial environments.

With proven project experience in plateau, desert, and polar regions, Kerun ensures all products deliver stable, efficient, and long-term reliable performance even under harsh environmental conditions.

Yes. Every transformer undergoes comprehensive routine tests and type tests before leaving the factory. Additional special tests are also performed according to project or customer requirements.
Kerun’s testing center is fully equipped to conduct all tests in compliance with IEC, GB, and IEEE standards, ensuring every unit meets performance and safety specifications before shipment.

1. Routine Tests

Performed on every transformer to verify compliance with design specifications:

• Measurement of voltage ratio and vector group;
• Measurement of impedance voltage and load losses;
• Measurement of no-load losses and no-load current;
• Insulation resistance, applied and induced voltage tests;
• Partial discharge tests;
• Temperature rise and sound level checks;
• Dimensional and visual inspection of accessories.

2. Type Tests

Conducted on representative units or new designs to validate performance and endurance:

• Temperature rise test;
• Short-circuit withstand test;
• Lightning impulse and switching impulse tests;
• Partial discharge and insulation verification;
• Transformer oil dielectric and chemical analysis;
• Noise and mechanical vibration assessment.

3. Special Tests

Executed upon customer request or contractual requirements, including:

• Online partial discharge monitoring;
• IP protection level verification;
• Seismic and vibration testing;
• Electromagnetic compatibility (EMC) tests;
• Corrosion and climatic aging tests;
• Third-party witness tests (SGS, KEMA, CE, UL, etc.).

4. Test Reports and Witnessing

• Each transformer is supplied with a comprehensive routine test report;
• Type test or third-party test reports are available upon request;
• Clients and consultants are welcome to witness the testing process on-siteand review live data;
• All test results are digitally archived for full traceability and can be provided in both electronic and hardcopy formats.

Kerun follows a “100% tested, fully traceable” quality policy to guarantee that every transformer meets design and standard requirements before delivery — ensuring reliability, safety, and customer confidence.

Regular maintenance and inspection are key to ensuring the stable, safe, and long-term operation of oil-immersed transformers. At Kerun, we provide a comprehensive maintenance and service plan to maximize the performance and lifespan of your transformers. This article outlines our detailed regular maintenance schedule, designed to meet the various needs of our customers.

1. Importance of Regular Maintenance

Transformers are crucial components of power systems, and their stability directly impacts the reliability and safety of power supply. Kerun understands that factors like operational environment, load conditions, and external environments can all affect transformer health. To ensure optimal performance and extend transformer life, we offer a detailed set of maintenance services for regular and emergency care. These services aim to keep the transformer running efficiently, minimizing the risk of downtime and unexpected failures.

2. Kerun's Oil-Immersed Transformer Maintenance Plan

Daily Maintenance (Monthly or Quarterly)

Daily maintenance is the foundation for ensuring the continuous operation of your transformer. Kerun recommends performing monthly or quarterly basic checks, including the following:

• Oil Level Check: Ensure the oil level is within the normal range to maintain the cooling system’s effectiveness.
• Oil Color and Temperature Check: Monitor the color and temperature of the oil, ensuring there are no signs of contamination or overheating.
• Insulation Resistance Check: Test the insulation resistance of the transformer’s components to ensure safe operation.
• Mechanical Check: Inspect the external structure for any damage, cracks, or vibrations that could indicate issues.
• Cooling System Check: Verify the proper functioning of the cooling system, including oil pumps and fans.

Semi-Annual Maintenance (Every 6 Months)

Every six months, a more detailed maintenance procedure is recommended. This includes:

• Oil Sampling and Testing: Collect oil samples for dissolved gas analysis (DGA) and assess the quality of the oil to detect potential issues.
• Load Current Measurement: Measure the load current and assess whether it aligns with the rated value.
• Connection Check: Inspect all electrical connections for tightness, ensuring they are free from corrosion or wear.

Annual Maintenance (Once a Year)

Annual maintenance is a comprehensive checkup to ensure long-term safe operation. It includes:

• Insulation Resistance Testing: Measure the insulation resistance across key components to ensure they meet design standards.
• High-Voltage Testing: Perform high-voltage tests to assess the transformer's insulation performance.
• Internal Cleaning: If necessary, clean the transformer’s interior to remove dust and foreign objects that could affect its operation.

Major Overhaul (Every 4-6 Years, or as Needed)

For transformers that have been in service for an extended period, a major overhaul is recommended. This includes:

• Disassembly and Inspection: Completely disassemble the transformer to inspect critical components, including the core, windings, and electrical connections.
• Mechanical Testing and Servicing: Check for mechanical wear, corrosion, or damage and replace components as needed.
• High-Voltage Testing: Perform high-voltage tests to verify the integrity of the insulation system.
• System Optimization and Upgrades: Based on operational conditions, upgrade systems and optimize cooling performance or install monitoring systems.

3. Flexibility and Customization of Maintenance Plans

Kerun understands that each client has unique operational conditions and requirements. Therefore, we offer flexible and customized maintenance plans based on the specific needs of each customer. Whether it’s extreme weather conditions, harsh environments, or specific industry requirements, Kerun tailors its maintenance services to ensure maximum uptime and efficiency.

We work with clients in large-scale industrial sectors, including power generation and critical infrastructure, offering full lifecycle services from transformer selection and installation to long-term maintenance. This ensures that your equipment is always in optimal condition, minimizing downtime and extending transformer life.

4. Benefits of Kerun's Maintenance Services

Professionalism and Experience

Kerun’s maintenance team consists of highly skilled engineers and technicians with extensive experience in the field. They are capable of providing professional and accurate maintenance services for all transformer models.

Complete Lifecycle Support

From design and manufacturing to installation, commissioning, and after-sales service, Kerun offers a complete solution to ensure that your transformer operates efficiently for its entire service life.

Remote Monitoring and Diagnostics

For transformers equipped with smart monitoring systems, Kerun offers real-time diagnostics and remote monitoring. This allows us to continuously track the transformer’s performance and identify potential issues before they lead to failures.

5. Conclusion

Kerun’s comprehensive oil-immersed transformer maintenance and service plan is designed to ensure the long-term, reliable, and safe operation of your equipment. Through regular inspections, oil testing, high-voltage assessments, and more, we provide a tailored approach to transformer maintenance. This plan maximizes equipment performance, reduces downtime, and prolongs the life of your transformer.

For detailed maintenance plans or customized services, please contact us. Kerun is committed to providing you with the best solution to keep your transformers running at peak performance.

Kerun is committed to offering comprehensive after-sales support to ensure that oil-immersed transformers maintain optimal performance and reliability throughout their life cycle. Our services cover troubleshooting, equipment repair, technical support, and regular maintenance. Below are the key after-sales services we provide:

1. Technical Support
2. a) 24/7 Customer Support
   Kerun provides 24/7 customer support. Whether it is during regular working hours or outside of them, customers can reach our technical support team at any time. We offer consultations on transformer-related technical issues, troubleshooting guidance, and repair instructions to ensure uninterrupted operation.
3. b) Remote Monitoring and Diagnostics
   For certain models of transformers, Kerun offers remote monitoring services. Customers can view real-time operational data, and our system automatically monitors the health of the equipment, sending alerts when issues are detected. We can also provide diagnostic services to ensure continuous optimal performance.
4. Troubleshooting and Diagnostics
5. a) On-Site Troubleshooting
   If an issue cannot be resolved remotely, Kerun will dispatch experienced engineers to the site for troubleshooting. Our team will identify the root cause of the failure and implement effective measures to restore the equipment to normal operation.
6. b) Fault Analysis and Reports
   After a failure, Kerun provides detailed fault analysis and reports. By examining the failure source and conducting on-site inspections, we propose corrective actions and preventive measures to avoid future issues.
7. Maintenance and Replacement Services
8. a) Transformer Maintenance
   Kerun provides regular maintenance services, including oil replacement, core inspection, winding cleaning, and more. Regular maintenance ensures the transformer is operating at its best and extends its service life, preventing unnecessary breakdowns.
9. b) Spare Parts Supply
   If parts of the transformer are damaged, Kerun will supply necessary spare parts promptly. We maintain a robust parts inventory system to ensure timely replacement and minimize downtime.
10. c) Oil Replacement Service
    Oil is critical for transformer insulation and cooling. Kerun provides professional oil replacement services to maintain the transformer’s insulation performance and effective cooling function. We periodically check and replace the oil to ensure the transformer’s long-term reliability.
11. Extended Warranty and Long-Term Maintenance Options
12. a) Standard Warranty Service
    Kerun provides a standard warranty service for each transformer, typically lasting 12 to 36 months. During the warranty period, we provide free repair or replacement services if any issues arise.
13. b) Extended Warranty
    For customers seeking longer coverage, Kerun offers extended warranty options. This ensures continued support, including maintenance, troubleshooting, and technical assistance.
14. Operator Training and Support
15. a) Operator Training
    We offer training for customers' operators to ensure proper use and maintenance of the transformer. Through training, your operators will learn how to prevent common issues and improve operational efficiency.
16. b) Maintenance Training
    Kerun also provides maintenance training to help your technicians master transformer repair and upkeep skills. The training includes common fault diagnosis and preventive measures, helping your team increase operational expertise.
17. Upgrade and Retrofit Services
18. a) Equipment Upgrades
    Kerun offers equipment upgrade services to enhance the performance of transformers. We add modern features such as remote monitoring, automation, and improved control systems to optimize transformer operation.
19. b) Retrofit Services
    For older equipment, we provide retrofit services. We tailor solutions to extend the transformer’s service life and enhance performance.
20. Predictive Maintenance Services

Kerun provides predictive maintenance services to track the health of transformers. By analyzing data from remote monitoring, we predict potential issues and take proactive measures to prevent failures before they occur.

8. Documentation and Reports

After each maintenance or repair service, Kerun provides detailed service reports, including test results, maintenance actions, and post-service status. These reports allow customers to fully understand the equipment’s condition and history, aiding in future management decisions.

9. Emergency Support and Fast Response

In the event of a critical failure, Kerun guarantees fast response times. We ensure that a technical team is dispatched promptly to the site to restore normal operation and minimize downtime, ensuring that your operations continue without disruption.

10. Technical Documentation and Resources

Kerun offers comprehensive technical documentation, including product manuals, operation guides, and repair manuals. Customers can access these resources at any time to better manage and maintain their transformers.

At Corun, we are committed to providing fast and efficient spare parts support to ensure that transformers are restored to normal operation as quickly as possible in case of issues. Below are some detailed points regarding spare parts availability, delivery time, and costs:

1. Spare Parts Availability and Delivery Time:
   • Standard Spare Parts:
     For common standard spare parts (e.g., cables, connectors, seals), we ensure a quick delivery time. The delivery time for standard parts typically ranges from 2 to 3 weeks, depending on stock availability and delivery location. If the parts are in stock, faster delivery is possible.
   • Special Spare Parts:
     For customized special spare parts (e.g., custom oil tanks, high-voltage electrical components), the delivery time may be longer, usually 4 to 6 weeks, depending on the complexity of the product and material requirements. If customers need highly customized products, it is advisable to contact us in advance for proper arrangement.
   • Emergency Spare Parts:
     In the event of an emergency failure, Corun can provide emergency spare parts through our global supply chain, ensuring the quickest possible restoration of the equipment. The delivery time for emergency spare parts is typically 1 to 3 days, with priority given to critical components.

2. Typical Cost of Spare Parts:

• Common Spare Parts:
  For common parts like cables and connectors, the price typically ranges from $1,000 to $4,000, depending on the model and specifications.
• Special Spare Parts:
  For certain special parts, such as high-voltage oil tanks or custom electrical components, the price generally ranges from $3,000 to $5,000, and the exact price will vary depending on customization.
• Oil and Oil Filtering Systems:
  For oil and filtering systems used in special operating conditions, the price typically ranges from $5,000 to $20,000, depending on the capacity and design requirements.

3. Spare Parts Procurement and Ordering Process:

Corun offers a convenient spare parts ordering service. Customers can place their orders through our online platform or directly contact the sales team. We ensure the quality of the spare parts and strictly control delivery times. In urgent situations, Corun provides priority procurement services to ensure that customers receive the required parts in the shortest time possible.

4. Conclusion:

Corun's spare parts supply and after-sales service system provide reliable support to ensure that transformers maintain high-efficiency operation. Whether it's standard, special, or emergency spare parts, we meet customer needs efficiently and minimize downtime, ensuring that equipment remains operational.