CONNECTION BY FOLDED-SEAM METHOD AND DEVICE FOR ITS MAKING Russian patent published in 2005 - IPC

FIELD: ventilation and air conditioning.

SUBSTANCE: connection by tight folded seam of two flexible metal pipes, sections of pipelines, segments or elbows of pipes used to transmit flows of gas is provided with double fold in form of flange at end of first pipe enclosed by second double fold made on end of second pipe at least with partial adjoining to shape and provision of enclosing solid metal sealing. Connection is formed by outward flanging universal bending or edging machine provided with forming rolls installed for rotation and feed rolls installed fro displacement in one plane. Said rolls are set into motion by motor and project from machine table. At first stage of operation double in form of flange is made on end of first pipe, and at second stage, step member is formed on end of other connected pipe. Width of step member exceeds size of double bend in form of flange. At third stage member is driven over double bend and projecting part of step member is pressed tightly to double bend with enclosing of bent and provision of sealing. Shifted lower roll of device is made in form of hollow shaft accommodating drive shaft carrying axially secured forming roll. Feed roll is made in form of hollow shaft which accommodates drive shaft carrying upper shifted forming roll. Feed roll and lower are mounted in slides to provide synchronous displacement. Rolls are also installed in slides for displacement in direction of axially secured forming roll and shifted lower roll.

EFFECT: provision of high tightness of connection.

4 cl, 11 dwg