SAUER DANFOSS SERIES 90 VOLUMETRIC HYDRAULIC DRIVE REPAIR METHOD Russian patent published in 2023 - IPC B22D19/10 B23P6/02 B24B37/11 

FIELD: mechanical engineering.

SUBSTANCE: method for repairing a Sauer Danfoss series 90 volumetric hydraulic drive includes hardening the surface of the soldering of the cylinder block, finishing on a grinding and polishing machine and restoring the holes. The soldering surface of the cylinder block is hardened on an electric spark installation with a molybdenum electrode, followed by mechanized finishing on a grinding and polishing machine. The holes in the body of the back cover for the spool are restored with blind adjustable diamond reamers on a precision machining unit. On the surface of the pistons and the spool of the body of the rear cover, a metal coating of medium carbon steel is deposited on an electric spark unit in a mechanized mode. The welded surfaces of the pistons and the spool are ground on a centreless machining unit until the gaps in the piston to cylinder block bushing hole connection are 15-24.9 microns, and gaps in the spool to rear cover housing hole connection are 5-11.6 microns.

EFFECT: increase of physical and mechanical properties of applied metal coatings on the surfaces of restored parts is provided.

1 cl, 1 tbl, 1 ex