One-Piece Lost Mould for Metal Castings and Method for Producing It

Abstract

In the case of a one-piece lost mould for metal castings 4 of a set moulding material which encloses a mould cavity and has at least one metallic cooling channel 6 that is embedded in the moulding material and carries a cooling medium, portions of the outer side of the metallic cooling channel 6 are uncovered and/or only slightly covered by the moulding material in the direction of the mould cavity.

1 : One-piece lost mould for metal castings ( 4 ) of a set moulding material which encloses a mould cavity and has at least one metallic cooling channel ( 6 ) that is embedded in the moulding material and carries a cooling medium, wherein portions of the outer side of the at least one metallic cooling channel ( 6 ) are uncovered and/or only slightly covered by the moulding material in the direction of the mould cavity. 
   
   
       2 : Mould for metal castings ( 4 ) according to  claim 1 , wherein the at least one cooling channel ( 6 ) is smooth-walled and has a wound or oval cross section. 
   
   
       3 : Mould for metal castings ( 4 ) according to  claim 1 , wherein the at least one metallic cooling channel ( 6 ) is a flexible metal tube, a flexible corrugated metal tube or a wound corrugated metal tube. 
   
   
       4 : Mould for metal castings ( 4 ) according to  claim 1 , wherein the at least one metallic cooling channel ( 6 ) is formed from steel or high-grade steel. 
   
   
       5 : Mould for metal castings ( 4 ) according to  claim 1 , wherein plaster or a ceramic compound is used as the moulding material. 
   
   
       6 : Mould for metal castings ( 4 ) according to  claim 1 , wherein a moulding base material that contains a binder is used as the moulding material. 
   
   
       7 : Method for producing a one-piece lost mould for metal castings ( 4 ) according to  claim 1 , comprising the steps of:
 forming a lost pattern ( 3 );   enclosing selected regions of the lost pattern ( 3 ) with at least one cooling channel ( 6 ),   embedding the lost pattern ( 3 ) that is enclosed by the at least one cooling channel ( 6 ) in a moulding material which can be made to set, while providing a gating and feeding system ( 12 ),   making the moulding material set, and   removing the lost pattern ( 3 ) by melting or burning or gasifying.   
   
   
       8 : Method according to  claim 7 , wherein the lost pattern ( 3 ) is a wax pattern, plaster is used as the moulding material and the wax pattern is melted away after the setting of the plaster mould. 
   
   
       9 : Method according to  claim 7 , wherein the lost pattern ( 3 ) is a wax pattern, a ceramic compound is used as the moulding material, the wax pattern is melted away after the setting of the moulding material and the ceramic mould is fired. 
   
   
       10 : Method according to  claim 7 , wherein the lost pattern ( 3 ) is an expanded polystyrene or plastic pattern, a moulding base material that contains a binder is used as the moulding material, and removal of the lost pattern by burning or gasifying only takes place by the molten metal itself when it is poured off.