Extruder and cylinder exchanging method thereof

摘要

In an extruder of the invention, a screw receiving portion penetrates through a cylinder from one connection surface to the other connection surface thereof and the connection surface of the cylinder is connected to the connection surface of other cylinder, a key groove for positioning the other cylinder and a recess having a taper surface are formed in at least one of outer wall surface of the cylinder except the connection surface thereof, and a wedge portion of a connection member is pressed into the recess to connect adjacent cylinders.