METHOD AND PLANT OF PRODUCING TUBES WITH SPIRAL RIBS Russian patent published in 2011 - IPC B21C37/20 

FIELD: process engineering.

SUBSTANCE: invention relates to production of ribbed tube from various metals and alloys for use in heat exchangers. Proposed method comprises twisting the tube with outer lengthwise ribs with local heating. Simultaneously with local heating of tube section inert gas is fed onto tube outer surface between zone of local heating and that of tube end clamping to cool tube down to t ≤ 350°C. Proposed plant comprises loading flute to support tube being twisted in interaction with twisting sleeve fitted in the mechanism of its turning, local heating inductor through which tube is fed, tube feed mechanism made up of drawing unit and tapered mandrel with axial bore that enters tube inside, tube heated section intensive cooler arranged behind twisting sleeve and made up of perforated sleeve through which the tube is fed, and inert gas feed source communicated via hoses with cooling sleeve and mandrel connected with drawing unit with tapered mandrel.

EFFECT: tubes with minimised oxidised layer to be removed in subsequent thermal treatment, higher quality and lower costs.

4 cl, 5 dwg, 1 ex