The main beam

The main girder is also called the inner frame, which forms the backbone of the roadheader with the support device system. Both of these structures are made of thick steel plates with high strength. The main girder and the saddle are connected by advancing the hydraulic cylinder. The relative movement between the main girder and the saddle is achieved by advancing and retracting the hydraulic cylinder. The front end of the saddle is connected with the hydraulic cylinder for advancement, and is slidably connected with the main girder through the slider. Under the effect of the propelling cylinder, the main girder can move in the saddle frame through the slider.