About Kerosene vapor-phase drying equipment
Kerosene vapor-phase drying equipment
Kerosene vapor-phase drying equipment (KVPD) is mainly suitable for drying transformer bodies in super-high voltage than 110kV and big capacity.
Working Principle
Under heating and vacuum condition, liquid kerosene will become vapor in high temperature. When vapor meets workpieces in less temperature, it will condense and release latent heat of condensation (about 306.6kJ/kg) which will heat workpieces. Condensed kerosene will be collected and re-transmitted to the evaporator to be heated again. In this way, under several cycles, temperature of workpiece increases continuously and moisture inside the workpieces evaporate to water vapor, to be taken out by vacuum and thus achieve complete drying on the workpieces.
Process Features
- Take kerosene as heating media which can carry heat and release heat by condensation. Kerosene condenses more acutely when there temperature is low. And so transformer body heating is more even.
- After kerosene vapor become liquid on the surface of workpiece, kerosene will also exchange heat with workpiece. And so the heat exchanging efficiency is higher than any other methods.
- Due to saturation pressure of kerosene is far less than that of water but higher than transformer oil, kerosene can be evaporated very quickly without effecting diffusion coefficient of water at high vacuum phase.
- Since heating is under vacuum without oxygen, when temperature raised from 110 to 130, insulation materials will not age; On the same time, the partial pressure of water vapor will be increased to 9.8104Pa, which quickens moisture evaporating speed.
- Condensed kerosene is very easily infiltrated into the surface and internal of insulation material to accelerate its own thermal conductivity and to make deep temperature of insulation material is distributed uniformly (which is very important for drying)
- Condensed kerosene is also a very good cleaning solvent. It can wash out dust and dirt on the workpiece. This is very special feature only available on the KVPD drying. And so this kind of KVPD drying equipment is especially suitable for treating repairing transformers.
Technical features of VPD
- It is equipped with build-in cascade evaporator, which can carry out distillation between two heating phases.
- There is an individual heat recovery device outside of tank, saving energy
- Water extraction quantity in each phase and total extraction amount can be recorded on time and displayed on computer screen. Water extraction curve of each intermediate pressure reduction phase and total water extraction amount curve can be drawn instantaneously. And water extraction rate of each intermediate pressure reduction phase can be calculated automatically.
- The flow of kerosene in the mixture of kerosene & water can be measured instantaneously and so the opening rate of the main control valve can be controlled accurately, but not only rely on tank pressure control.
- The end point can be measured automatically by computer. The process will be cut off automatically when the temperature of workpieces reaches 1205, and tank pressure is less than 0.2mbar and water extraction rate is less than the set value.
- The whole process can be fully controlled automatically, and even can be operated unattended. The computer can monitor the process of product and display process parameters and curve of each phase. Various process curve and reports can be printed timely and backup automatically.
- Visible & audible alarm can be done automatically. And usual troubleshooting methods can be provided. Malfunction point and time can be recorded timely.
- Various parameters and the implementation state of program can be saved when power failure suddenly.
- Process parameters can be displayed and revised.
Specifications
- Tank size: 7000 x 4500 x 4500mm~16000 x 6000 x 7000mm (as required)
- Heating power: 250kW~600kW (based on tank size)
- Max. working temperature: 135 5
- Temperature controlling precision: 5
- Ultimate vacuity: 10MPa (non-load)
Advanced Drying Technology for Electrical EquipmentUtilizing kerosene vapor-phase heating, this equipment ensures efficient, deep drying of transformers and electrical apparatus, surpassing traditional air-drying methods. Forced convection promotes thorough moisture removal, safeguarding insulation quality.
Flexible, Customizable Design for Diverse NeedsWith customizable sizes, kerosene tank capacities, and power sources, the KVPD-Series adapts to a wide range of transformer specifications and client requirements, ensuring optimal fit and function across varied operational sites.
Safety and User-Friendly OperationIntegrated overtemperature protection, safety interlocks, and a robust door design enhance operational safety. The intuitive touchscreen HMI and PLC automatic control streamlines monitoring, while keeping noise levels below 75 dB(A) for a more comfortable workspace.
FAQs of Kerosene vapor-phase drying equipment:
Q: How does the kerosene vapor-phase drying process work in the KVPD-Series equipment?
A: The process uses kerosene vapor, heated in a controlled environment, to penetrate and evaporate moisture from transformers and other electrical equipment. Forced convection circulates the vapor evenly, driving moisture out rapidly and effectively.
Q: What types of transformers and electrical equipment can be dried with this equipment?
A: The KVPD-Series is suitable for a range of transformers and insulated electrical apparatus, accommodating loads up to 5000 kg per batch and volumes from 500 liters to 15,000 liters. Internal and external dimensions can be customized to fit different sizes and types.
Q: When is vapor-phase drying recommended over conventional drying methods?
A: Vapor-phase drying is recommended when rapid, thorough moisture removal is essentialparticularly for large power transformers or equipment with complex insulation systems. This method significantly reduces drying time and improves final insulation resistance compared to conventional air drying.
Q: Where is the equipment typically installed and operated?
A: These drying systems are used in transformer manufacturing plants, repair facilities, and electrical equipment workshops. As the external and internal sizes are customizable, the units can be designed to fit the available site layout and infrastructure.
Q: What safety features are included in the KVPD-Series to protect users and equipment?
A: The equipment includes overtemperature protection, safety interlocks, a seal-tight heavy-duty door, and advanced PLC controls. These features ensure operational safety by preventing overheating, accidental access, and unsafe operation conditions.
Q: How do users operate and monitor the drying equipment?
A: Operation is managed through a user-friendly touchscreen HMI panel with PLC-based automatic control. Users can set parameters, monitor drying progress, and adjust settings as needed, ensuring precision and repeatability in every batch.
Q: What are the main benefits of using the KVPD-Series vapor-phase drying oven?
A: Key benefits include faster and more uniform drying, enhanced transformer core and insulation longevity, customizable configurations, high energy efficiency, and comprehensive safety measures. These advantages result in superior equipment reliability and reduced turnaround times for manufacturers and service providers.