The wall thickness distributions in longitudinal sections hydromechanically bulged axisymmetric components made from copper and steel tubes

Purpose: The paper presents experimental results that concern hydromechanical bulging of copper and P265TR1 steel axisymmetric component whose relative wall thickness was s0/D=0.04 (where s0 is the wall thickness and D is outer diameter of tube segments). Design/methodology/approach: The basic parameters of the hydromechanical process of bulge forming are: liquid pressure and axial loading. The process is employed while manufacturing pipe connections, including axisymmetric components. Copper pipe connections are used in hydraulic, heating, gas and waste water systems. The technology involves placing a tube segment in a die-cavity, pouring some liquid over it, and sealing the faces. Findings: The experimental investigations, described in the paper, on hydromechanical bulge forming of copper and P265TR1 steel axisymmetric component with the ratio h/d1=0.67 (where h is height and d1 is diameter of spherical cup) aimed to compare the wall thickness distribution in longitudinal sections of axisymmetric components. Besides it, the aim of experimental inwestigations was to compare patterns of pressure changes and force at relative displacement up to ∆l/l0=0.06. Research limitations/implications: The results obtained in the experiment might be used as guidelines to develop a technological process for manufacturing such type of connections with the method of hydromechanical bulge forming. They also could be helpful while applying the method to industrial practice. Originality/value: The experimental investigations, described in the paper aimed to determine the possibility of hydromechanical bulge forming of axisymmetric components made from copper and steel tubes, compare force waveforms at the constant upsetting ratio, compare distribution of wall thickness.