Flat aluminum wire and copper stranded conductor welding technology for oil-immersed type distribution and transformation product

Abstract

The invention discloses a flat aluminum wire and copper stranded conductor welding technology for an oil-immersed type distribution and transformation product and belongs to the technical field of transformers. The flat aluminum wire and copper stranded conductor welding technology comprises the steps of 1 preparing a transition copper bar, 2 removing insulated paper at the end of a copper stranded conductor, 3 calculating the lap joint length during welding according to the section areas of the flat aluminum wire and the transition copper bar, 4 removing a paint film on a to-be-welded area ofthe flat aluminum wire, 5 welding copper wires at the end of the copper stranded conductor into a whole, 6 heating one end of the transition copper bar on a platform and melting a phosphor copper welding rod on the lap joint face between the transition copper bar and the copper stranded conductor, 7 placing the copper stranded conductor on the face where the copper stranded conductor and the transition copper bar are welded and conducting heating until welding flux flows into a weld joint to fill and level up the weld joint, 8 placing the other end of the transition copper bar on the platformand melting copper-aluminum welding wire on the lap joint face between the transition copper bar and the flat aluminum wire, 9 placing the flat aluminum wire on the face where the flat aluminum wireand the transition copper bar are welded and conducting heating until welding flux flows into the weld joint and fills and levels up the weld joint, and 10 removing welding slag and welding powder ofa welded connector with an iron brush and a flat file and finally conducting insulating wrapping.

Description

technical field [0001] The invention belongs to the technical field of transformers, and in particular relates to a welding process of aluminum flat wires and copper stranded wires for oil-immersed distribution transformer products. Background technique [0002] At present, the high and low voltage coils of traditional oil-immersed distribution transformer products are made of copper foil and wire, and because the voltage level of oil-immersed distribution transformer products is below 35kV, the cross-sectional area of ​​the wire rod is large, and the high-voltage coil lead wire and tap The switch needs to be connected by transition welding of copper stranded wires to ensure the flow cross section and product operation performance. First, use a welding torch to remove the paint film at the ends of the coil leads, and pre-weld the ends of the copper strands to be welded together with solder; secondly, start welding to preheat the coil leads, and when the leads are heated to a...

AI Technical Summary

Problems solved by technology

This process is only suitable for oil-immersed distribution transformers whose high and low voltage products are made of copper. At present, the market finds that some customers purchase oil-immersed distribution transformers whose high and low voltage coils are all aluminum. After the stranded wire is welded, it is connected to the tap changer. Since the welding melting points of copper and aluminum are different, and the welding process of copper stranded wire is prone to cracking or false welding, the welding problem of aluminum flat wire and copper stranded wire has become a market issue. The bottleneck of receiving orders for oil-immersed all-aluminum distribution transformer products, and it has brought certain difficulties to the development of the market in this field