High-stiffness winding core

Abstract

A winding core has high stiffness by virtue of being formed predominantly of fiber-reinforced plastic (FRP) such as fiber glass material or the like. In particular, the winding core comprises a tubular shell of FRP, and a pair of generally tubular end fittings bonded to the inner surface of the shell at the opposite ends, the end fittings comprising a material having a durometer hardness substantially lower than that of the shell and being positioned to be engaged by wind/unwind chucks. Each end fitting has an axial length that is a relatively small fraction of the length of the shell.

1 . A winding core, comprising: 
 a fiber-reinforced plastic shell of cylindrical form, the shell having an outer surface and an inner surface and having opposite ends; and    a pair of generally tubular end fittings bonded to the inner surface of the shell at the opposite ends, the end fittings comprising a material having a durometer hardness substantially lower than that of the shell and being positioned to be engaged and frictionally gripped by chucks inserted into the opposite ends of the shell.    
   
   
       2 . The winding core of  claim 1 , wherein the end fittings comprise a coating of said material applied to the inner surface of the shell.  
   
   
       3 . The winding core of  claim 2 , wherein the material comprises polyurethane.  
   
   
       4 . The winding core of  claim 1 , wherein the shell has a length between the opposite ends sufficient to accommodate a wound material having a width of about 4.3 meters.  
   
   
       5 . The winding core of  claim 1 , wherein the shell has a nominal inside diameter of about 76 mm and a radial thickness of about 14 to 18 mm.  
   
   
       6 . The winding core of  claim 1 , wherein the shell has a nominal inside diameter of about 130 to 150 mm and a radial thickness of about 9 to 17 mm.  
   
   
       7 . The winding core of  claim 1 , wherein the shell has a nominal inside diameter of about 200 to 300 mm and a radial thickness of about 13 mm.  
   
   
       8 . The winding core of  claim 1 , wherein the shell has a nominal inside diameter of about 415 mm and a radial thickness of about 13 to 16 mm.  
   
   
       9 . The winding core of  claim 1 , wherein the shell has a nominal inside diameter of about 570 mm and a radial thickness of about 13 to 17 mm.  
   
   
       10 . The winding core of  claim 1 , wherein each of the end fittings has an axial length of about 50 to 300 mm, and the shell has an axial length exceeding 1 meter.  
   
   
       11 . The winding core of  claim 1 , wherein each of the end fittings has a radial thickness of about 1 to 6 mm.