Patent EA-004490-B1 (EA)
Title: Cooling element and method for manufacturing cooling elements
Inventor: POLVI VEIKKO
IPC: F27D9/00
Filed: 2001-02-21
Abstract: 1. A cooling element designed particularly for furnaces, said element comprising a housing (1) mainly made of copper, and a channel system (6) provided in the housing for cooling medium circulation, characterized in that at least in part of the surface of the element housing (1), there is arranged, by means of a diffusion joint, a corrosion-resistant surface layer (2) made of steel. 2. A cooling element according to claim 1, characterized in that the surface layer (2) is made of refined steel. 3. A cooling element according to claim 1 or 2, characterized in that the surface layer (2) is provided only on part of the surface of the element housing (1). 4. A cooling element according to any of the claims 1-3, characterized in that the cooling element is a flash smelting furnace cooling element. 5. A cooling element according to any of the claims 1-4, characterized in that the cooling element is a cooled so-called chute element particularly used for conducting melt. 6. A method for arranging a corrosion-resistant surface layer in a cooling element consisting mainly of copper, characterized in that the surface layer (2) made of steel is attached to the element housing (1) by means of a diffusion joint, wherein between the surface layer (2) and the junction surfaces of the housing (1), there is arranged at least one intermediate layer (3) consisting mainly of nickel (Ni) or chromium (Cr) or of an alloy or mixture thereof prior to creating the joint. 7. A method according to claim 6 or 7, characterized in that the employed surface layer (2) is made of refined steel. 8. A method according to any of the claims 6 or 7, characterized in that in between the surface layer (2) and the junction surfaces of the cooling element housing (1), to be joined together, there is arranged a first intermediate layer (3) on the junction surface of the surface layer (2) or against said surface, and a second intermediate layer (4) on the junction surface of the housing (1) or against said surface, so that the junction surfaces including their intermediate layers are pressed together, and at least the junction area is heated. 9. A method according to any of the claims 6-8, characterized in that the second intermediate layer (4) consists of an activator with a melting temperature that is lower than the melting temperature of the objects to be joined together. 10. A method according to any of the claims 6-9, characterized in that the second intermediate layer (4) consists mainly of silver (Ag) and/or tin (Sn), or as an alloy or in a mixture, silver and copper (Ag+Cu), aluminum and copper(Al+Cu) or tin and copper (Sn+Cu). 11. A method according to any of the claims 6-10, characterized in that there is brought at least a second intermediate layer (4) and at least a third intermediate layer (5), and that the melting temperature of the second intermediate layer (4) is lower than that of the third intermediate layer (5). 12. A method according to any of the claims 6-11, characterized in that the third intermediate layer (5) consists mainly of silver (Ag) or of silver (Ag) and copper (Cu) either as an alloy or in a mixture. 13. A method according to any of the claims 6-12, characterized in that the junction area is heated in one step. 14. A method according to any of the claims 6-13, characterized in that the second intermediate layer (4) is brought on the surface of the third intermediate layer (5). 15. A method according to any of the claims 6-14, characterized in that at least one of the intermediate layers (3,4,5) is brought to the junction area in the form of foil.