Mathematical modeling and experimental Investigations on forming force during tube spinning of AA6061☆☆

In present research, a mathematical model based on dimensional analysis for estimating resultant force has been proposed for single roller backward tube spinning along with experimentations. Tube spinning is also known as flow forming process which is generally used to produce ultra precise thin-walled tubes for aviation, aerospace and defense application. The prediction of forces are important aspects for accurate tooling design and desired output of formed components. Therefore, an attempt has been made to propose a mathematical model to predict the resultant force. Subsequently, an indigenous experimental test rig has been developed to measure the force elements. Three operating parameters (speed, feed and reduction) and two tooling parameters (roller nose radius and leading angle) were considered for experiments. The operating variables were considered at three levels and tooling variables are taken for two levels for suitable robust experimental design (Taguchi L₃₆). Single roller backward spinning was adopted with the AA6061 as blank material as it is normally used aluminum alloy due to its intense applications. It has been observed that the axial force is found to be highest among other two components of forces i.e. radial and circumferential. Also, it has been found that the resultant force is mainly influenced by forming depth. It means, higher the forming depth, higher the resultant force. The proposed model was trained and tested against experimental data. The adequacy of the model was checked by various quantitative measures. The initial information can be obtained about resultant force with the use of the model to design the roller for different material conditions.