Process and apparatus for replacing cathodes

A process for replacing the cathodes of rectangular cells in an electrolytic plant in which said cells are positioned side by side in rows perpendicular to the longitudinal axes of the cells, each cell having a plurality of sequentially numbered cathodes suspended vertically at equal distance from one another and perpendicular to the longitudinal axes of the cells, wherein cathodes having an electrolytic deposit thereon are removed from said cells and replaced with cathodes from which said electrolytic deposit has been removed, comprising the steps of:

• (a) lifting a first subgroup comprising the even-numbered cathodes from a first cell and simultaneously lifting a second subgroup comprising the odd-numbered cathodes from a second, adjacent cell while maintaining the orientation and disposition of said even-numbered and odd-numbered cathodes, thereby obtaining two subgroups of cathodes offset from one another along the longitudinal axes of said first and second cells over a distance equal to the distance between two adjacent cathodes;
• (b) conveying said subgroups to a stripping installation while moving said subgroups perpendicular to the longitudinal axes of said cells until a collinear unstripped set of cathodes is formed from said even-numbered and odd-numbered subgroups, said stripping installation having an entry for cathodes having an electrolytic deposit thereon to be stripped and an exit for stripped cathodes;
• (c) placing said collinear unstripped set of cathodes at the entry of said stripping installation;
• (d) lifting a collinear stripped set of cathodes from the exit of said stripping installation, said collinear stripped set having sequentially numbered stripped cathodes equal in number, orientation and disposition to said collinear unstripped set;
• (e) conveying said collinear stripped set of cathodes to two adjacent cells while separating said collinear stripped set into a third subgroup comprising the even-numbered cathodes and a fourth subgroup comprising the odd-numbered cathodes of said collinear stripped set, said separating achieved by moving said third and fourth subgroup perpendicular to the longitudinal axes of said cells until said third and fourth subgroups are in the same relative position as the first and second subgroups of said first and second cells, respectively;
• and
• (f) simultaneously placing the cathodes of said third and fourth subgroups in two adjacent cells, from which the respective even-numbered and odd-numbered cathodes have been removed, in the positions from which a first and a second subgroup have been removed.