100 cutting gun 150 steel plate can be cut through manually?

100 cutter gas cutting 150 steel plate can't be cut through. When gas cutting thick steel plate, due to uneven heating of the workpiece, the lower metal burns slower than the upper metal, and the incision is easy to form a large resistance, even can not be cut through, and the slag is easy to block the lower part of the incision, which affects the smooth progress of gas cutting process.