Research On Hydraulic System Of Drilling Tool Conveying Device

In the process of continental scientific drilling operations, to extract the core, there is need for hundreds to thousands of drill pipes, core pipes and casings to make frequent tripping and discharge operation. Tripping and drilling tool processing time account for more than a third of all operation time, and the accident caused by drilling tools transportation takes up more than 79% of all drilling accidents. At present, it mainly relies on four or five workers together to accomplish drilling pipe up and down from the drilling platform, and operation time ranging from 3 to 7 minutes. If the migration of casing, longer time is required. In this drilling tool transport approach, there is workload of workers, poor operation reliability, serious damage of drilling tool, and higher safety accident frequency.If using drilling tool conveying device to transport drilling tool, the entire process takes only 1 to 2 workers, and the migration time ranging from 50 seconds to 3 minutes. Not only can raise the efficiency of drill tool up and down from the drilling platform, but also can reduce the workload of workers, make shorter the operation cycle of the whole rig integrated system, improve the level of mechanization and automation of drilling equipment facilities, so there is a wide application prospect of researching on automatic drilling tool conveying device.This article is based on the project belonging to Ministry of Land Resources of “Deep Continental Scientific Drilling Equipment Development of the Special Project of Deep Exploration Technology and Experimental Research”, and takes hydraulic system of drilling tool conveying device the research topics. Mainly focusing on studying load sensing feature, and characteristics and optimization design belonging to hydraulic pipeline of hydraulic system of drilling tool conveying device.Firstly, describes structure composition and operating principle of drilling tool conveying device, illustrates functions of the main structure in detail, and establishes the basic structure diagram of the hydraulic system. Secondly, designs hydraulic system principle diagram, analyzes its operating principle, calculates relevant parameters, and selects the model of main hydraulic components. Then, establishes mathematical model of key hydraulic components including load sensing pump and load sensing multiple unit valve, and HCD simulation model in the AMESim software. To analyze flow control characteristics and high pressure cut-off features of load sensing pump, and pressure compensation function of load sensing multiple unit valve. Next, establishes mechanical model of key structure consisting of transferring system and hoisting system with the PLM Library in AMESim software, and conducts both hydraulic simulation analysis to study the flow and pressure change rule. Subsequently, makes a reasonable layout of the hydraulic pipeline, analyzes the influence of hydraulic pipeline for hydraulic system on power consumption, cavitation and hydraulic shock, and establishes pipeline bending vibration equation. With the minimum pipeline energy loss and the minimum pipeline volume as the optimization goal, the optimization design of the pipeline is carried out, which obtains the optimal pipe diameter and flow velocity. Finally, through experimental verification, it proves that hydraulic system design of drilling tool conveying device is reasonable, has good working performance, and can also meet the work requirement.