what is the distance between the columns

 in the bending machine parameter table? 

What's the use?

 The distance between the two side plates of the bending machine is the distance between the columns. The position of the columns is shown in the red box in the figure below, and the distance between the columns is shown in the red arrow in the figure below. The function is to support the bending machine, and the column spacing limits the length of the processing material. If the length of the processing material exceeds the column spacing, but is less than the length of the worktable, the deepest processing width of the processing material is the throat depth.