The analysis of factors influencing the trajectory of the vibrating screen
Authors: Fedoliak N. V. , Liakh М. М. , Mykhayliv V. V. 
Published: September 2021

Due to the fact that the shape of the trajectory of the sieve vibrating screen significantly affects the efficiency of cleaning the drilling mud from the drilled rock, this article identifies and analyzes the factors influencing the formation of the trajectory of the sieve. The study of the nature of the motion of the particles of the drilled rock is carried out. The motion-equation of the point of the jigging frame, respectively, and a certain section of the screen can be described by an non-homogeneous second-order differential equation (Newton equation). The equation of the trajectory of the jigging frame is also considered. The influence of the amount of drilling mud, which is on the vibrating screen at a certain time-point, on the trajectory is taken into account in this equation. The drilling mud complex system consisting of liquid and solid fractions – sludge, sand and sludge – is taken into account. In this case, the fluid and clay move without separation from the sieve, and sludge and coagulated clay – with separation from the transport surface. Depending on the position on the sieve, each component of the drilling mud at different time periods moves with different trajectories and different other variable parameters along the length of the sieve. Therefore, the main purpose of the research is to obtain a graphical real trajectory of the selected point of the jigging frame of vibrating screens, to compare it with theoretical graphical dependences and to establish parameters that affect the change in the amplitude of jogging frame vibrations in real operating conditions. The coverage of the problem and the main results of the research are performed in real conditions (when vibrating screens work on the drilling rigs). The research is performed using simple recording devices installed at six places – on the left and right sides of the jigging frame above the front and rear shock absorbing springs, and in the center of stuff – between springs. All the real trajectories of certain points of the jigging frame and screen can be described using  certain Lissajous figures. However, it was found that not all trajectories coincide completely with the classic Lissajous figures, because the trajectory is influenced by external factors that cause chaotic motion of the jigging frame – the Sommerfeld effect, as well as non-uniformity of drilling fluid delivery. The nature of the movement of the vibrating plane - the screen - is also affected by the rigidity of the vibrating support, including the entire structure of the vibrating screens. The phenomenon of resonance is possible in the area of ​​vibration supports. In addition, it was previously established that the trajectory of the point of a certain area of ​​the screen is a spatial figure that requires additional theoretical and experimental studies. When moving the drilling fluid on the sieve with the toss, the cleaning efficiency will be much higher due to the increase in vibration force. Based on the analysis of the results of the factors influencing the trajectory of the sieve, preliminary recommendations are given for the correct adjustment of the vibrating screen.