The power grid system is used for workers in the welding workshop to operate welding machines, electric tools and pneumatic tools quickly and conveniently, and provides welding machine placement, power supply, gas source, lighting and other needs for workers in the work process to improve workers‘ work efficiency and product quality. Socket boxes and mixed gas joints are often arranged on the power grid columns of the bus welding line to meet the needs of welding work; spring-structured pneumatic joints and electric joints are often arranged on the power grid columns of the bus assembly line to meet the requirements of the bus assembly line to plug in pneumatic tools or electric tools.