PROCESS OF FIXING PIPES IN PIPE GRATES Russian patent published in 2001 - IPC

FIELD: plastic metal working. SUBSTANCE: process can be used to fix pipes in pipe grates of heat exchange equipment with utilization of effect of localized directional plastic deformation of material of pipe. Ring protrusion of trapezoidal section is made on external surface of end of pipe, ring recess equidistant to pipe hole is made on face surface of pipe grate. Pipe is put into pipe hole of pipe grate having internal and external annular grooves. In this case end of pipe protrudes beyond face surface of pipe grate, ring protrusion of pipe is matched with external ring groove of pipe hole. Pipe is fixed against possible movement and anchored in pipe hole by application of compressing force to internal surface. Then protruding end of pipe is heated, compressing force is applied to its butt to secure plastic flow of heated material of pipe over surface of mentioned-above ring recess with formation of butt ring seal between pipe and pipe grate. Ring recess can have the form of triangular or stepped cross-section. EFFECT: increased tightness of obtained joints. 2 cl, 6 dwg