Investigation of dynamic processes in the hydraulic system of clamping the staffs of the segment unwinder of the unit of aggregation of rolls pipe welding machine 20-114

Abstract

In the technological line for the production of small diameter pipes used segment un-winder staffs with a cantilever drum and additional support. The experience of its operation has shown that one of its main shortcomings is the unsatisfactory operation of the hydraulic system clamping staffs. In the hydraulic clamping system of the staffs there are increased dynamic loads, which lead to the failure of components and elements of the hydraulic system. The layout of the hydraulic clamping system of the headquarters is made for design and technological rea-sons, without taking into account the influence of pipeline lengths on the nature of dynamic processes in the hydraulic system. In addition, the hydraulic system uses spool hydrodistributors with electro-hydraulic control, the operation time of which is practically not subject to regulation. Based on the analysis of known mathematical models for the study of dynamic processes in hydraulic systems, it was concluded that as a mathematical model that takes into account the design and operation of the hydraulic clamping system staffs finite-difference method in a sys-tem of ordinary differential equations with boundary conditions described by algebraic equations. A basic dynamic model has been created, which allows to analyze with high relia-bility the behavior of the hydraulic system of the clamping mechanism of the staff in the segment unwinder of the rolls, which is exposed to different nature in a wide range of mode parameters. Simulink MATLAB software environment was used to effectively solve this problem. During the implementation of the mathematical model, a study of the modes of operation of the hydraulic system of the clamping mechanism of the staff was performed. It was found that at the end of the working and reverse strokes of the clamping mechanism of the roll in the end posi-tions there are dynamic loads in the hydraulic system that reach the maximum allowable values. In addition, it was found that during the acceleration of the piston of the hydraulic cylinder during operation and reverse, although there are no dangerous loads, but there are rapid fluctuations in pressure in the cavities of the hydraulic cylinder. Theoretical studies of the modes of operation of the hydraulic clamping system of the staff in the segment unwinder with different operating times of the control valve. As a result of the study of transients in the unwinding hydraulic system with different operating times of the hydraulic distributor, its ra-tional operating time was recommended, which is 0.20 seconds when opening and 0.15 sec-onds when closing.