Design And Theoretical Research On Drilling String Conveying Equipment

With the development of science and technology, the development of automated drilling speed faster and faster. Abroad studied the string automated processing technology since the 1990s, quick string conveying equipment has developed into a frontier drilling technology, which is also the main direction of drilling technology in the 21st century.The traditional string assignments require people to cooperate to complete, operating persons are labor intensity, high risk and low working efficiency, workers are prone to injury accidents. At the same time, modern drilling development direction are in deep well, ultra deep wells, large displacement horizontal well. With the increase of well depth, the drilling site need more string and the transportation of string will be large, therefore the drilling site need strong transport capacity, fast speed of tool sends string to rig. Based on the understanding of the various conveyer on the basis of both at home and abroad and the deep discussion of the conveying equipment automation processing system has carried on, an automatic string conveying equipment designed to adapted to ZJ70, drilling depth of 4500m-7000m, rig maximum height of 10.5 m. The automatic string conveying equipment can effectively improve the on-site safety, reduce the labor intensity of the workers and implement the concept of health, safety, environmental protection.In this paper, we have carry out the research which corresponding of string conveying equipment, research content mainly includes five aspects, the mechanical structure design, the statics and kinematics analysis, dynamics analysis, performance analysis and finite element analysis of key parts. Concrete content as follows.First of all, analyzing the present situation and problems of development and application string automated processing system and string conveying equipment. Organize the related information and data, understand the characteristics of the main types of string conveying equipment. According to the actual working condition of the string conveying equipment and its requirements, determine the structure and main parameters of the conveying system and the storage system.The string conveyer storage system is mainly composed of string stored inside box and the outer box. The store number of drill pipe is higher than 450, the string inside box contained ten groups of storage tank, each group of storage tank can accommodate 12 drill pipe, so a single storage inside box can store 120 drill pipe. In order to save space and guarantee the drill pipe can rolling in the inside box, the height of each storage cabinet is 150 mm, the height of the storage box is 2040 mm, the width, of the storage box is 1645 mm. Combining with the design of storage inside box structure, design the out box is compose of security frame, columns, pillar, storage, hydraulic cylinder, pulleys, etal. The length of outer box is 12 m, the width of outer box is 2.1 m, the maximum height of outer box 2.28 m, the maximum lifting force of outer box is 1484 kN. The conveying system is mainly composed of pipe racks, base assembly, the rotation arm assembly, transmission arm assembly, ramp assembly, hydraulic winch and other structures, it can be used with the storage system. The string conveying equipment can send the string from the ground to the drill floor, or transfer the string from the drill floor to the ground.Secondly, finished the design according to the function requirement of each components, draw the 2d drawing of conveying system and storage system by CAD software, complete 3d model of the equipment by Solid works, introduces the composition and working principle of the string conveying equipment in detail. Set up a simplified model to conveying system. To complete statics model of the conveying system combined the method of statics and geometric equations, which providing a theoretical basis for conveying system performance analysis.With the structure and working principle of conveying system, established the the geometric equations of the structure and statics equations in the of process of lifting while lifting in the first, second, third and fourth stages. Through the established geometric equation, combined with practical work the derrick floor height is 10.5 m, slope Angle is relatively fixed, the largest angle of rotation arm is limited and other design requirements, calculated the structural parameters of the conveying system under the given conditions. Combine the final structure parameters and the statics equations, calculated the maximum tension of conveying system is 92635 kN, which is less than the maximum tension value of system can provide, the tension meet the design requirements.Third, the dynamics equations of the four stages during the conveying system lifting was established based on D’Alembert’s principle and relevant statics models, the dynamics equations solve through the c# and Matlab software. Analyses the the largest lifting force and the maximum slope upward force during the lifting. The structure of string conveying equipment is proved feasibility. At the same time, analyzed the influence of main parameters on the lifting force and slope upward force.The dynamics of the conveying system mainly takes into consideration the inertial force of the conveying arm and the rotating arm, the change of the geometric equation in the third and the fourth stage, the equilibrium equation to establish the dynamic equations of each stage by every stage of the geometric equations and the equilibrium equation. The software calculation results show that the maximum tension of the system under the regular work is 81230 N. the maximum tension under the maximum working load is 131380 N. So the maximum lift are less than the maximum lift force of the hydraulic winch, meets the using requirement. The outstretched length of conveying arm are between 1.5m and 5.5m, the height less than 2.6m, it can satisfy the requirements of field to use. In the end of dynamic analysis, through the software analysis the effect of tension and ramp support to ascension differ from the offset e, the end length of conveying arm, the length of rotation arm, the weight of wire rope string, and etal,, which provide reference for structural and parameters optimization.Finally, analysis the strength and stability of the key parts of the conveying system and the storage system, some key components of system are analyzed in statics, verified the deformation and stress conditions of the key parts. Analysis the stability of main hydraulic cylinder rod, which safety provides standard of safety and reliability to key components of the system.In statics analysis, analyzes the maximum stress and deformation figure of the rotate fixed seat、the pipe racks and pipe racks of hydraulic lever、the baffle of pipe racks and the wire rope connecting pin while they are in the most extreme working conditions and under the biggest force. The results showed that the intensity of each parts can satisfied the demands of their respective material strength.In the stability analysis, by comparing first five order buckling modal of storage hydraulic lever、block hydraulic lever、flap hydraulic lever and maximum working load of each hydraulic cylinder rod and maximum working load of each hydraulic cylinder rod. The results showed that the each various order buckling load is greater than the each maximum load of the each hydraulic cylinder rod and the stability of each hydraulic cylinder rod meet the requirements.