Screws are widely used in plastic molding equipment, such as plastic profile extruders and injection molding machines. The screw and barrel are the core components of plastic molding equipment. They are the parts that heat, extrude, and plasticize the material. They are the core of plastic machinery. Screws are widely used in machining centers, CNC machines, CNC lathes, injection molding machines, wire cutting machines, grinding machines, milling machines, slow wire EDM, fast wire EDM, PCB drilling machines, engraving machines, CNC milling machines, EDM machines, gear grinding machines, planers, large vertical lathes, gantry milling machines, etc.
For cases where the screw tail is floatingly connected to the gearbox spindle, since the screw floats in the barrel, the bending stress caused by the screw's own weight is zero. Therefore, only the compressive and shear stresses of the screw are calculated. 2) Because the bending stress caused by the screw's own weight is very small (the screw is surrounded by material), even in the first case, it can be neglected. Therefore, these two methods are actually the same. 3) There are also methods that estimate the screw diameter based on torque.