Plasticizing barrel lined on the inside with a coating, and method of making such a plasticizing barrel

Abstract

A plasticizing barrel for a plastics processing machine includes a body having a hollow cylindrical configuration and defining an axis; and a coating formed on an inner wall surface of the body and including at least one groove extending in axial direction of the body. The coating, e.g., a wear-resisting protective layer, may be produced through centrifugal casting, whereby the grooves are formed by projections of a negative mold inserted in the hollow-cylindrical body.

1 . A plasticizing barrel for a plastics processing machine, comprising: 
 a body having a hollow cylindrical configuration and defining an axis; and    a coating lining an inner wall surface of the body and including at least one groove extending in axial direction of the body.    
   
   
       2 . The plasticizing barrel of  claim 1 , wherein the at least one groove has a helical configuration.  
   
   
       3 . The plasticizing barrel of  claim 1 , wherein the coating is a wear-resisting protective layer.  
   
   
       4 . A negative mold for carrying out a method of making a plasticizing barrel for a plastics processing machine, comprising a base body defining an axis and formed with projections extending in direction of the axis, said base body defined by a diameter which is smaller than an end inner diameter of a plasticizing barrel lined on an inner wall surface with a coating.  
   
   
       5 . The negative form of  claim 4 , wherein the base body with the projections define an outer diameter which is smaller than the inner diameter of the hollow-cylindrical body by twice a thickness of the coating.  
   
   
       6 . The negative mold of  claim 4 , wherein the base body has a cylindrical configuration.  
   
   
       7 . The negative mold of  claim 4 , wherein the projections have a surface lined with at least one coating selected from the group consisting of adhesion-reducing coating and wear-reducing coating.  
   
   
       8 . The negative mold of  claim 4 , wherein the projections extend in axial direction of the base body and has, in the direction in which the negative mold is removed from a hollow-cylindrical body, at least a configuration selected from the group consisting of increasing width in circumferential direction and increasing height in radial direction.  
   
   
       9 . The negative mold of  claim 4 , wherein the projections have a helical configuration.  
   
   
       10 . A negative mold for carrying out a method of making a plasticizing barrel for a plastics processing machine, comprising a cage defining an axis and including projections extending in direction of the axis.