TUBE EXPANDER Russian patent published in 1998 - IPC

FIELD: machine engineering, namely tube expanding in openings of tubular heat exchangers of other equipment and joining tubes with tube walls by welding along outer perimeter of tube end. SUBSTANCE: tube expander includes two pistons mounted on rod. Ends of said pistons have cone outer surfaces. Expander also includes arranged between said pistons sleeve for expanding tube, changeable spacing sleeve and loader. Sleeve for expanding tube is in the form of set of sector slide blocks mutually joined in radial direction by means of elastic ring members in such a way that said sleeve may engage with pistons mounted on rod by means of reciprocal cone end surfaces. EFFECT: increased reliability, lasting operation life of apparatus, high quality of tube expanding in opening of tube wall. 4 cl, 1 dwg