METHOD OF ROLL CHOCKS HYDRAULIC CYLINDER PLUNGER RESTORATION WITH FUSING Russian patent published in 2008 - IPC B23P6/02 B23K9/04 

FIELD: technological processes.

SUBSTANCE: invention may be used for restoration of plungers of hydraulic cylinders in roll chocks of cold and hot rolling. Preliminary heating is done up to temperature of 200...300°C. Multi-layer fusing is done with steel electrode with the rate of 30...40 m/h with density of electric current of 20...25 A/mm² with maintenance of plunger temperature in the process of fusing of not higher than 300°C. Electrode of the following composition is used for fusing, weight %: carbon 0.01...0.20, manganese 1.20...1.80, silicon 0.50...0.90, chrome 10.0...20.0, nickel 5.0...10.0, iron - the rest. Further thermal treatment of plunger is done at temperature of 250...300°C with time delay of 3...4 hours.

EFFECT: reduction of flow rate of roll chocks hydraulic cylinder plungers by increase of plunger surface wear resistance.

2 cl, 2 tbl, 5 ex