Study And Development Of The Traction Apparatus For Polymer Melt Spouted-accumulated Forming Process

In order to satisfy the growing demand for large diameter plastic pipes manufacturing,various kinds of large diameter plastic pipe forming technology were put forward by scholars from countries in the world.One of the technologies,the polymer melt spouted-accumulated forming technology,which was put forward by Chinese scholar and combined the concept of additive manufacturing with extrusion molding,can realize the large diameter plastic pipe continuously manufacturing without mould.The study and development of the traction apparatus for polymer melt spouted-accumulated forming process play a pivotal role in promoting this new technology.Firstly,common structures of traction apparatus and its relative research status at home and abroad were summarized,and critical technologies of the area from international and domestic scholars were deeply understood in this paper.After the polymer melt spouted-accumulated forming technology was briefly introduced,an apparatus using for pipe linear and rotary traction was put forward according to the requirement of the technology.Secondly,the structure of the traction apparatus was designed,dimensions and strength were calculated according to mechanical theories and the motors for clamping,linear traction and rotary traction were chosen.According to the control flow of traction apparatus,the control system designing was completed with TIA Portal,including hardware selection,PLC programming,HMI interface designing and so on.And the 3D CAD modeling of traction apparatus was finished with Solidworks.Then,the finite element analysis for traction apparatus was carried out with ANSYS Workbench,including static analysis,modal analysis and harmonic response analysis.Through the analysis,it was found that the maximum stress of the apparatus was 107.85 MPa while the allowable stress was 180 MPa,which meant the maximum stress was much less than the allowable stress and there was still plenty of room for optimization.The working frequency of traction apparatus was much lower than its natural frequency,which meant it was less likely to resonate and had good anti-vibration performance.Basing on the analyses above,optimization of the traction apparatus structure was proceeded,including the optimization of the frame,the tray and the caterpillar track component.The weight of the traction apparatus decreased from 4549.6kg to 4126.52 kg,which meant it declined by 9.3%.In the same time,the static analysis and modal analysis showed that the requirement of strength and stiffness were meet,and it was less likely to resonate at work.The traction apparatus after optimization was manufactured and assembled by the company Dekuma Rubber & Plastic Technology(Dongguan)Co.,Ltd.,where the author of this paper had internship.Then clamping function,linear traction function and rotary traction function were tested.Finally,the large diameter plastic pipe spouted-accumulated forming experiment was carried out,and pipes with high quality were produced whose parameters were diameter 800 mm,wall thickness 20 mm and pitch 10 mm.