Liner bolt and removal apparatus therefor

Abstract

A liner bolt ( 1 ) for securing a liner to a mill, the liner bolt ( 1 ) comprising a head ( 3 ) and a shank ( 4 ) extending therefrom, the shank ( 4 ) having an external thread thereon, and having a bore ( 5 ) therein extending from its free end. A removal pin ( 2 ) is adapted to be inserted into bore ( 5 ) when liner bolt ( 1 ) is to be removed from the mill. Removal pin ( 2 ) is adapted to be struck by a moil ( 14 ).

1 . A liner bolt for securing a liner to a mill, said liner bolt comprising a head and a shank extending therefrom, said shank having an external thread thereon, characterized in that said shank having a bore therein extending from its free end. 
   
   
       2 . A liner bolt as claimed in  claim 1 , wherein in use, when said liner bolt is to be removed from said mill a removal pin is inserted into said bore. 
   
   
       3 . A liner bolt as claimed in  claim 2 , wherein in use said removal pin in is adapted to be struck by a moil. 
   
   
       4 . A liner bolt as claimed in  claim 3 , wherein said moil is operably mounted to a liner bolt removal tool. 
   
   
       5 . A liner bolt as claimed in  claim 4 , wherein said moil is housed within an adaptor mounted to said liner bolt removal tool, and said adaptor is adapted to slidably engage with said pin. 
   
   
       6 . A liner bolt as claimed in  claim 1 , wherein in use when said liner bolt is to be removed from said mill a moil is adapted to be inserted into said bore. 
   
   
       7 . A hammer adaptor for a liner bolt removal tool, said adaptor adapted to be fitted to said tool in such a manner to shroud said moil, said adaptor slidably engagable with a liner bolt and a removal pin, said liner bolt comprising a shank having a bore therein and said removal pin adapted to be seated within said bore, said adaptor to guide said moil into striking engagement with said pin. 
   
   
       8 . A hammer adaptor as claimed in  claim 7 , wherein said hammer adaptor is length variable. 
   
   
       9 . A hammer adaptor as claimed in  claim 8 , wherein said hammer adaptor comprises a first tubular member spring loaded in a telescopic arrangement with a second tubular member. 
   
   
       10 . A removal pin in combination with a predetermined liner bolt, said predetermined liner bolt comprising a head and a shank extending therefrom, said shank having an external thread thereon, and said shank having a bore therein extending from its free end, said removal pin having a first end adapted to be inserted into said bore of said liner bolt, and a second end adapted to be struck by a tool when said removal pin is in engagement with said liner bolt. 
   
   
       11 . A liner bolt for securing a liner to a mill, said liner bolt comprising a head and a shank extending therefrom, said shank having an external thread thereon, said shank being of length such that when said bolt is secured to said mill, a substantial portion of said shank protrudes from said mill, thereby allowing a hammer adaptor for a liner bolt removal tool to slidably engage with said shank. 
   
   
       12 . A liner bolt as claimed in  claim 11 , wherein said hammer adaptor is length variable. 
   
   
       13 . A liner bolt as claimed in  claim 12 , wherein said hammer adaptor comprises a first tubular member spring loaded in a telescopic arrangement with a second tubular member.