Roots Vacuum Pump for Transformer Drying

Roots Vacuum Pump for Transformer Drying

Transformer Manufacturing

Vacuum drying is a critical manufacturing process for transformers, involving the removal of moisture and gases from the transformer body under negative pressure. This procedure enhances dielectric strength before final assembly and oil filling.

Kerosene vapor phase drying (KVPD) is the predominant method for transformer drying, surpassing circulating hot air, hot oil, and variable-pressure vacuum processes in heating uniformity, speed, and effectiveness.

Core Mechanism:
Special-grade kerosene acts as a heat transfer medium within a vacuum chamber. When heated, kerosene vapor penetrates the transformer body due to its:

1. Lower specific heat capacity vs. water (2.0 kJ/kg·K vs 4.18 kJ/kg·K)

2. Higher saturated vapor pressure in the 50–100°C range
   These properties enable rapid volatilization that extracts residual moisture while simultaneously flushing out particulate contaminants.

Critical Advantages:

• Zero residue: Post-drying evaporation eliminates >99.9% kerosene

• Self-cleaning effect: Removes dust/metal particles from windings

• Performance enhancement: Boosts dielectric strength by 15–25% vs conventional methods

The vacuum solution commonly used in kerosene vapor drying process is the Oil-lubricated rotary vane Roots vacuum system.

Usually, a high-flow oil-sealed rotary vane pump is used as the pre-stage pump, and a Roots vacuum pump is used as the main pump. The Roots pump improves the pumping speed and vacuum of the entire vacuum system.

Oil-Lubricated Rotary Vane Rotts Vacuum System

#Customer Case

Recently, a customer needed to replace the Roots vacuum pump in the transformer vacuum drying system. Based on his needs, we recommended our magnetic Roots vacuum pump LCVS-1200, which provides a pumping speed of 1200L/s.

Wordfik provides one-stop vacuum solutions