This machine consist of 4 parts of driven systems, inclusive Master plate of Rotation, Plate of push reinforcing steel, expansion diameter part, and welding machine. The 4 parts are drived by independent electrical motor. The Full variable frequency control ensures that the span of the latitude steel and the angle of the spigot won't not change along with the welding speed.

Adjustment the ratio of motor speed can change the span of latitude steel, and angel of spigot. This machine can weld different diameter cages via adjustment of location and position of the master plate and welder.