Research On The Contour Surface Type And Performance Of The Roller Rolling Groove Of The Iron Roughneck’s Punching Pliers Speciality:Fluid Power Transmission And Control

As an important part of the iron roughneck,the broaching pliers can provide sufficient torque when the drill(pipe)string is up and down.In the process of shackle,the pliers will apply a large clamping force and torque,which will easily make the pliers bite into the outer wall of the drill(pipe)column and damage it.The two-way self-locking roller push-off clamp replaces the clamp teeth with rollers.Compared with the conventional push-off clamp,it increases the contact area with the drill(pipe)column,reduces the contact stress of the pipe,prolongs the service life and improves the work efficiency.Therefore,it is of great significance to study the self-locking roller punching pliers in the field of oil drilling.This paper is based on the design concept of using the guide rail,gear transmission and hydraulic cylinder to achieve the purpose of continuous up and down.Firstly,the scheme design of the self-locking roller punching clamp mechanism is carried out,and two schemes are formed.The second scheme is the structure of continuous rotary roller punching clamp.The following work is designed on the basis of the structure of scheme.Secondly,the type and self-locking performance of the roller rolling groove of the impact clamp are analyzed.The mechanical analysis model and self-locking mathematical model of the roller rolling groove are established.The finite element simulation is used to calculate the mathematical model error.According to the self-locking condition,it is judged whether the five contour surface contact forms can reach the self-locking state,and a reasonable contour surface is selected according to the analysis results.Thirdly,in the form of the rolling groove contour surface of the mechanical model,the Ansys finite element software is used to analyze the finite element statics of the roller and the rolling groove of the snap clamp,and the sensitivity analysis of the rolling groove surface parameters(surface length,base circle radius,etc.)on the self-locking performance is studied.Finally,taking the maximum self-locking margin as the objective function,the parameters of the roller and the rolling groove as variables,the constraint conditions that the radius ratio and the center angle are less than the maximum rotation angle are determined to ensure the smooth motion of the roller.The genetic algorithm is used to optimize the self-locking performance of the main parameters of the roller and the roller rolling groove contour surface,and the self-locking performance is improved by 8.81 %.In this paper,a continuous rotating iron roughneck punching clamp is designed to improve the working efficiency.The mathematical model of self-locking of roller rolling groove is established,which makes up for the lack of self-locking mathematical model of roller punch clamp in scientific research.The sensitivity analysis of the self-locking performance of the parameters of the rolling groove surface is carried out,and the surface parameters with the least influence on the self-locking performance are selected.The parameters of the roller and the rolling groove were optimized,and the designed roller clamp was 8.81 % higher than that of the predecessors.