DC Power Medium Frequency Rolling Seam Welder for Round Shape Metal Welding DESCRIPTION 1. The current is rectified in order to supply DC welding current. 2. Helps to reduce the energy of iron core material. 3. The frequency of welding transformer is promoted from 50/60Hz of mains supply to 1000Hz. Transform the electric energy into DC power. FEATURE 1. Energy Saving: Compare with using low frequency, it can help to reduce the consumption of electric energy. The transformer