METHOD AND TUBE BENDING UNIT FOR MANUFACTURING COMPLEX SHAPED COILS FROM ELONGATE TUBE LENGTHS Russian patent published in 1995 - IPC

FIELD: heat-exchange equipment. SUBSTANCE: method involves forming solid end portion forming main portion and terminating the process by forming second solid end portion, with main portion being formed by applying tensile force within the range of plastic deformation to straight portion of tube length retained by pressure members of axial compression mechanism till preliminary compression force appears in portions subject to bending; measuring plastic deformation of tube portion between points of application of tensile force and using the value as initial set; gradually reducing deforming force and plastic deformation set to zero value in the process of bending, with plastic deformation of tube portion between points of application of tensile force being continuously measured and current value of distance between bending strickles being corrected and deviation of plastic deformation current value being taken into account. Tube bending unit for manufacturing complex-shaped coils has frame with guides for reciprocating tube-bending machines, which provide forming of main portion of flat coil of predetermined shape. Tube-bending unit is further provided with tube length feeding device, conveyance-accumulation device and bending control unit. EFFECT: increased efficiency of method, improved quality of coils and enhanced reliability in operation of bending unit. 4 cl, 21 dwg