in a plasticizing assembly for use in an injection molding machine , which assembly has a high - pressure chamber and a low - pressure chamber , which contains the feed screw , and a plurality of fixing screws disposed on a circular line , a connecting sleeve is provided , which partly surrounds the plasticizing cylinder or a rear section of a bipartite plasticizing cylinder and surrounds also the nozzle body or a forward section of a bipartite plasticizing cylinder in part of its length and is secured to the plasticizing cylinder or to its rear section . the fixing screws are screwed in and axially supported in tapped bores of the connecting sleeve and at their end faces bear on abutment faces of the nozzle body or of the forward section of the plasticizing cylinder . as a result , a replacement of the nozzle body or of the forward section of the plasticizing cylinder can be effected in a simpler manner and more quickly and will require lower physical forces and a simpler implement and it is possible to supply energy at a higher rate .