Dynamic Research Of The Single Side Corrugated Machine

Corrugated board production line is an automatic production line, with the equipment developing towards automating and high speed in recent year, the competition of it becomes fiercer. Corrugated machine upgrades every day, on the basis of this, the new generation of corrugated machine emerges some problems like vibration and noise, corrugated roller wear and so on.The main content of this dissertation is to study the vibration problems of corrugated machine, which is the key machine of corrugated board production line. Corrugated machine is made of several key mechanisms, Pressure Roller Mechanism is one of them, which determines adhesive strength and uniformity of corrugated paper and face paper. Firstly, According to the principle of vibration,the dynamic model of a two degree freedom Pressure Roller Mechanism was built. Taking into account the nonlinear factor, nonlinear analysis was used to get the roll mechanism of natural frequencies of Pressure Roller Mechanism. Then the first four natural frequencies of the pressure roller was solved by ANSYS.Cassette Roller Mechanism(composed of upper and lower corrugating roller) is the heart of corrugated machine, the mechanism has the advantage of fast changing corrugated roller and improving the working efficiency. In the first place,the cassette mechanism was modeled based on mechanical vibration theory to compute the natural frequencies of it, then the modal analysis of upper and lower corrugated rollers were done in the ANSYS to obtain their model states and modes. Finally, to study on dynamic characteristics of cassette mechanism and the mesh stress in the process of corrugated paper forming,the transient analysis was applied by ANSYS.In the process of research it’s found that center high value and convex curve of the slender hollow structure of up and down corrugated rollers had great influence on the contact stress, so the optimal center high value was essential to be studied on, two different kind of models of up and down corrugated roller were built by respective means of mechanics of material and contact simulation analysis in ANSYS. Both of them can extract a kind of convex curve, then the advantages and disadvantages of them were discussed. Finally, how the different cylinder forces effected on the center high value and contact stress of down corrugated roller was analyzed.With the vibration test experiment on corrugated machine was done and the acceleration signal was processed by the Fourier and the Hilbert Transformation, the specialty of vibration signal was separately studied on in time domain and frequency domain. In the time domain, three times vibration tests with the cassette mechanism under three different constraints were done, in order to determine which kind of constraint was the best way to obtain the optimal vibration effect. From the frequency domain, not only the inherent frequencies of the dynamics model of pressure roller mechanism and cassette mechanism were compared with the vibration test, but also the inherent frequencies of up and down corrugated rollers and pressure roller were compared too, the above two mechanism models were validated and corresponding to them the improving plan was came up.Through dynamic analysis of the key mechanisms of corrugated machine and vibration test, the causes of the vibration of corrugated machine were found, the improvements were put forward, and the theoretical basis and reliable reference datum for the development of high speeding, lower vibration, lower noise corrugated equipment were provided.