The cylinders and the screw stems of model sj-45-50 extruder are made of high -quality alloy steel with optimum hardness and strong corrosion resistance after precision finishing and nitrogen treatment.FM-600 auxiliary machine can be freely adjusted within the limits of 700mm according to the technological requirements of different materials,and is fitted with a plug-in plate mechanism for making vest bag.The double-rolling and double-cutting coiling unit adaopts torque motor to keep proper tension and make even and roll-changing easy.