Simulation Study On Meshing Of Large Modulus Gear And Pinion

Gear and pinion drilling rig is a new type of active pressure drilling rig.Compared with traditional oil drilling rig,the rig has the characteristics of high transmission efficiency,simple structure,convenient migration,energy saving and environmental protection,low operating cost and high automation.It can solve the drilling pressure problem in horizontal well and large displacement well.Gear and pinion drilling rig use the meshing motion of gears and pinion to drive the top drive up and down,so the rig can provide both uplift and downforce.The gear and pinion transmission method is adopted to make the drilling machine have a faster drilling speed and has a great advantage in shallow drilling.This paper has been mainly analyzed the meshing performance of rack and pinion in the operation of drilling rigs.The meshing performance is mainly studied from the load carrying capacity and movement rule of rack and pinion.In the process of gear meshing,the bearing capacity of the gear and pinion is the most basic law of its meshing motion.The movement rule of gear and pinion is analyzed to study its meshing performance.To analyze the load capacity of gear and pinion,the maximum stress of rack and pinion has been analyzed to determine whether the strength meets the requirements.Therefore,the normal gear mesh movement can be ensured.Under the condition of limited lifting of the gear and pinion,the traditional calculation formula of the tooth surface contact strength and the root bending strength is used to calculate the tooth surface contact stress and the tooth root bending stress.Under the same conditions,the finite element analysis method has been used to establish a finite element model of the rack and pinion and apply loads and constraints.In order to ensure the accuracy of the finite element analysis,the gear rotation process is simulated statically,and the motion process of the two meshing cycles of the gear tooth is simulated and analyzed.The meshing position of the maximum stress and maximum value of a meshing cycle is obtained.Finally,the results of the traditional theoretical formulas are compared with the finite element analysis results to analyze the causes of the errors.The motion law of gear rack engagement has been analyzed,and the meshing dynamics model of rack and pinion has been established.Combined with the structure and movement law of gear rack lifting system,a dynamic model of lifting system has been established based on meshing dynamics model.Based on the dynamic simulation software,a simplified dynamic simulation model of gear rack lifting system has been set up.The dynamic simulation analysis has been conducted in 6 different working conditions.The simulation results of speed,contact force and others,have been obtained under each working condition,and the meshing motion law of gear pinion has been analyzed.The influence of gear design parameters on its bearing capacity has been studied.Single factor analysis and orthogonal test are adopted respectively.To ensure the accuracy and reliability of the analysis,take the lifting limit of the full hook limit of the drilling rig as the analysis condition,and select somewhere as the meshing position to analyse.The single factor analysis mainly analyzes the influence of gear module,tooth number,tooth width,displacement coefficient and pressure angle on the bearing capacity of gear,and obtains the corresponding influence rule.Orthogonal test has been conducted by 5 factors and 5 levels.25 groups of orthogonal experiments have been conducted.Range analysis and equation analysis have been applied to the data processing of orthogonal test respectively.The main and secondary relationship between the 5 factors on the bearing capacity of the gear and pinion,the optimal scheme of the gear carrying capacity and the significant factors affecting the bearing capacity of the gear and pinion in the 5 factors has been obtained from analysis.Considering that gear rack is always in low speed heavy load and frequent drilling,gear teeth are prone to fatigue failure or gear breakage.In the actual operation of gear and rack,the frequency of alternating load on the gear is much greater than that of the alternating load on the rack.This paper only takes the gear as the research object and analyzes its fatigue life.According to the load distribution law of drilling rig,the minimum running time of gear fatigue failure has been obtained combined with fatigue cumulative damage theory.In this paper,the analysis of gear and rack meshing characteristics is analyzed from two sides of the bearing performance and motion law of the gear.The research conclusions have been obtained.The conclusion of the research has the guiding significance to the design of the gear and pinion drilling rig as expected.