METHOD OF STABILISATION OF ELECTROPLATED CHROME COATING OF BARRELS OF AUTOMATIC SMALL ARMS, AND SHAFT-TYPE RESISTANCE FURNACE FOR ITS IMPLEMENTATION Russian patent published in 2015 - IPC C21D9/10 C21D1/76 F27B1/09 F27B1/14 F27D1/04 

FIELD: machine building.

SUBSTANCE: method of stabilisation of barrels of automatic small arms with electroplated chrome coating includes the barrels internal cavities filling with dry quartz sand and their installation in shaft-type resistance furnace, equipped with heat insulating partition with two heat zones at temperature in bottom heat zone 150-200°C, made in form of disk with holes for barrels installation using bushings with height 10-123 mm. At that breech end of the barrel is located above the heat insulating partition, and muzzle part under it are heated, and breech end is held at tempering temperature of hardened stub for hardness 38-44HRC, and muzzle part is held at temperature not exceeding tempering temperature of the barrel blank. The shaft-type furnace is equipped with heat insulating partition dividing the heating chamber to two sections, having individual electric heaters and creating two heat zones, made out of steel plates, and lined inside with light weight refractory material. In partition through holes are made for the barrels installation, and for their removal from the furnace on the partition the disk with eye lug is installed and aligned by kingpins. The furnace has second control cabinet.

EFFECT: increased wear resistance of the electroplated chrome coating of barrels, and absence of coating chips on the muzzle part of the barrels.

3 cl, 2 dwg, 1 ex