determination of the optimum loading path (internal pressure- axial feeding) to restrict the bursting, buckling and wrinkling through tube hydroforming process is necessary to produce an acceptable tube. in this paper, the wrinkling and fracture criteria are implemented to an finite element code devoted to the simulation of tube hydroforming processes. using the ansys parametric design language...

In ultrasonic tube hydroforming, the tube is hydro formed while the ultrasonic vibration is applied to the die. Prior studies provide experimental proof that ultrasonic tube hydroforming reduces corner radius, improves lubrication and uniform thickness. Use of ultrasonic vibration can decrease friction at the tube-die interface. Few attempts have been made to analyze the wire drawing while the ...

In this study, hot metal gas forming process of AA6063aluminumtubeis studied with a focus on heat transfer of both fluid and solid phases numerically. An experimental study is simultaneously conducted to validate the numerical method. Some of the most important outputs of the present study, are velocity distribution of fluid inside the tube as well as the fluid in the gap between tube and matri...

Background: With respect to physical relations in force and pressure, we hypothesized that the prevalence of traumatic tympanic membrane perforation in patients with a patulous Eustachian tube is greater than normal, because in Eustachian tube patency, the internal air pressure of the middle ear will not increase after compression, subsequent to trauma. Therefore the force upon the tympanic...

tube hydroforming (thf) process is used to produce the complex components from the initial cylindrical tubes. in this paper, t- shape component was formed using a tube hydroforming machine and the residual stresses of hydroformed tube was determined by hole drilling method. subsequently, the thickness distribution and residual stresses of final tube were investigated using experimental and fini...

one of the most prominent industries is bending, while using rotary draw bending method is known to be the most conventional approach for thin wall tube bending. pressure die is one effective tool which boosts the tube during the process and eventually improves the bending quality. other effective parameters are mandrel and the amount of clearance between tube and mandrel. in the present study,...

the cause of neural tube defects (ntds) is multifactorial and in this case folic acid has an important role. since the neural tube is closed during 21-28 days of pregnancy, most of women are not informed about their pregnancy at this time, and as a result the golden time of folic acid consumption is missed. the aim of this study was evaluating the performance of pregnant women attending to tehr...