Wire Feed System
The submerged arc welding machine of the wire feed control may be of the following types:
1. Voltage sensitive system
2. Constant wire feed
The voltage sensitive system operates on the principle of feed back control method. The wire is driven by a variable speed DC motor. The arc voltage is monitored by a sensing element, amplified and fed to the armature of the wire feed motor. Thus, the wire feed rate increases when the arc voltage rises up and vice versa. The arc voltage remains constant during the process. The constant wire feed system operates through a constant speed motor, usually an induction motor. No feed back control is used in this system. This system is used in conjunction with a constant voltage or constant potential characteristic power source. The arc voltage is constant in this system due to the self adjusting nature of the constant voltage power sourc