Structure Design Of Reverse Circulation With Wire-line Coring Tool And Numerical Simulation Study On Flow Field Of The Bottom Of The Hole

With the continuous development of economy, all kinds of prospecting technology is developing rapidly, but the geology core drilling technology is still the main means of prospecting. In the geolkogical prospecting coring drilling production, the Wire-line coring tool drilling technology has been widely recognized. In recent20years, our country’s geological enterprise vigorous development, expanding and deepening the investigation area, when encountered in the process of drilling production complex loose strata, the wire-line coring tool technology often encounter coring recovery rate, and back to the time the problem such as short footage cannot satisfy the requirement of geological work. Using spray against component features combined with the Wire-line coring tool technology advantage to become one of the feasibility of the solution to the problem, the current domestic research on the technology mature enough, it is not popularized and applied.First In this paper coring reverse circulation technique in this paper according to the complex loose stratum drilling enterprise problem, the wire-line coring tool reverse circulation drilling tools structure composed of theoretical analysis, designing increases the negative pressure reverse circulation channel seal structure, the suction device and control device. Negative pressure reverse circulation channel seal structure using radial sealing technology, and comparison on the sealing performance is more reliable; the suction device with double play card in place lock suspension positioning combined effectively prevents the hole pressure fluctuation; adjusting device including regulating system and feedback system, feedback system to guide the adjustment reverse circulation flushing fluid flow rate and core formation matches.The numerical simulation analysis was carried out on the structural parameters of the injector and research, By comparing different nozzle radius, reverse circulation flushing fluid and mud pump flow channel length for the effects of the reverse circulation drilling tool formation. Getting some conclusions. To get the optimal structure parameters, reasonable design of spray device sizes, improving the wire-line coring tool reverse circulation drilling tools in reverse circulation drilling and enterprising heart effect, ensure the quality of core.According to the numerical simulation analysis of the results, combining with technical advantage of wire-line coring tool drilling tools and drilling tool structure characteristics, the reasonable design of negative pressure reverse circulation channel seal structure, prevent suction device, adjusting device and the device position in drilling tool assembly, developed a set of can in complex loose and broken formation could satisfy the requirement of geological coring wire-line coring tool reverse circulation drilling tools.This paper designs the wire-line coring tool reverse circulation drilling tools, inherited the wire-line coring tool drilling tools in coring drilling technology advantage, namely to ensure the work efficiency and economic benefits of drilling production, and can be solved in the complex of lack of recovery rate in loosed and broken formation, low core quality problems.