Manufacturing of Bellows Compensator by Pulsed-Magnetic Field Pressure

Bellows are a cylindrical shell with a corrugated part, widely used in aviation engineering as a movable sealing element to balance pressure and temperature differences, which ensure continuous and accurate system operation. The use of bellows expansion joints provides reliable and effective protection of pipelines from static and dynamic loads arising from deformations and vibration. Welded-edge bellows are a popular choice for regulating and controlling fuel supply in aircraft devices. The ability of the compensator to perceive deformations is determined by its assigned operating time, which describes how many cycles, and with what amplitude, the bellows compensator perceives without damage. A method for stamping bellows from tubular billets by using magnetic-pulse field in rigid dies, including sequential shaping of corrugations by distributing the internal magnetic pressure with axial movement of the free end of a tubular billet, characterized in that the material of the tubular billet for shaping corrugations is selected in accordance with its relative elongation.

Scientifically substantiated technology for reverse extrusion of products made of anisotropic tubular billets

The theoretical research results of the reverse extrusion of a heavy-walled tubular billet made of orthotropic material having a cylindrical anisotropy of stress-strain properties are presented. The assessment of force modes and limiting potentialities of the reverse extrusion of anisotropic tubular billets is carried out.

Study of the Tubular Billets Geometric Characteristics during Computer Simulation of the Rotary Piercing Process

The results of the computer simulation of the tubular billet rotary piercing process are presented. The research methodology of the deformation zone geometric ratios with due regard for the tubular billet change of shape at each helical curve step was developed .The changes pattern of the helical curve step length (li), quotient reduction (Δr/r0), ratio of the tubular billet radius to the contact surface width (r/b), contact surface length of the tubular billet (l0) with a roll, depending on the feed angle (β), roll rotation frequency (N) and plug nose extension at the gorge (Сg) was established.

Influence of Deformation Conditions on the Power Regimes of the Process of Cold Crimping of a Pipe Billet in a Conical Die

An engineering technique has been developed that makes it possible to determine the power regimes of the process of crimping a tubular billet in a conical die, taking into account the effect of deformation conditions. The influence of the geometric parameters of the workpiece and tool, the crimping coefficient and non-contact deformation on the axial stress of the crimping process is studied. The main factors influencing the limiting values ​​of the workpiece crimping factor are established. Calculations are performed for the crimping process performed on an open circuit (without stop block), taking into account the friction and hardening of the material. The obtained results are in good agreement with the known experimental data and can be used in the development of the processes of crimping of pipe billets.

Some peculiarities of the process of the pipe purse firmware on the firmware

Purpose. Conducting research aimed at choosing the rational modes of flashing the tubular billet by stabilizing the dynamic characteristics of the drive power line of heavy-duty piercing mills TPA. Methodology. The dynamics of the power line of the piercing mill of the pipe-rolling unit (TPA) are considered, taking into account the peculiarities of the behavior of the spindle hinges and the mechanism for setting the work rolls. Findings. The differential equation of motion of the line of the main drive of the piercing mill is composed and its numerical solution is given. An adapted three-mass dynamic model of the system is considered and a solution is obtained using the software Solid Works IT Simulation X. The basic conditions for the occurrence of unstable dynamic phenomena in the fieldline and the installation mechanism of the piercing mill rolls are formulated. It is shown that the unstable dynamics of the system are one of the main reasons for the discrepancy between the results of well-known theoretical, experimental studies and pipe thickness measurement at TPA 350 piercing mills. Originality. The main causes of the emergence of parametric oscillations in the drive of the working stand of the piercing mill, the installation mechanism of the work rolls in connection with the mechanism of formation of the thin-wall thickness of pipes are established. The areas of stability of the system’s functioning are determined depending on the operating modes and the angle of feed of the work rolls, taking into account the spatial position of the elements of the spindle device. The necessary and sufficient stability conditions for the joint stable functioning of the power line elements of the piercing mill are formed. Practical value. To stabilize the processes for flashing the tubular billet, a scheme has been proposed for upgrading the spindles of the main drive and the mechanism for installing the work rolls of the piercing mill No. 1 of TPA 350. The results are applicable to similar helical rolling mills. Keywords: firmware, billet, mill, pipe, uneven stroke, varying thickness, dynamics, drive, roll, oscillations, spindle, Cardan, hinge, moment of inertia, rigidity, drum, installation mechanism, stability.

Numerical and Experimental Study of Producing Two-Step Flanges by Extrusion with a Movable Sleeve

The paper presents a new metal forming process for producing two-step external flanges on hollow parts. With this method, the flange is extruded by a movable sleeve, which moves in the opposite direction to the punch. This reduces the phenomenon of buckling of the tube wall, which allows extruding flanges with relatively large volumes. The new method was applied to produce a two-step flange on the end of a tubular billet made of 6060 aluminum alloy. This cold metal forming process was designed based on numerical simulations and experimental tests. The effect of the basic technological parameters on metal flow was investigated and limitations of the process were identified. The experimental results confirmed the possibility of forming a two-step flange with a diameter that is approximately twice as big as the external diameter of the tubular billet.