Area In A Horizontal Well Accidents And The Prevention And Treatment Of Complex

Contemporary horizontal well technology is one of the major oil and gas resources exploration and development technology of horizontal well has the outstanding characteristic of "high yield and less well". Gas accumulated in a proven at the end of2009and the basic proven geological reserves of2.27trillion cubic meters, which has proven reserves of871.5billion cubic meters, to become China’s largest gas field for the scale application of horizontal well development provides a good base for resources. Therefore on the basis of relative FuJiOu optimization screening of horizontal well development area of1892square kilometers, planning the deployment of horizontal1459mouth, build capacity of21.8billion cubic meters, the use of geological reserves of268.2billion cubic meters. But due to its special horizontal well technology, its accident and complex problems there are big differences compared with vertical Wells, horizontal Wells accident many influencing factors are complicated, and involve more than one domain, multiple disciplines, in this paper, the influencing factors are summarized from the geological lithology to drilling technology, on the basis of previous studies, the accident complicated factors are divided into three aspects: geological factors, physics and chemistry, and engineering factors, and put forward the corresponding prevention and treatment measures.This article through to the analysis of forefathers’research and field practice, for the gas block in a horizontal well drilling accidents arising from the complex problems, summed up and classified its influencing factors.Common accidents in drilling horizontal well, in a complex mainly monk ditch and LiuGuGou group formation leakage and shi feng group, stone box of borehole wall instability and collapse accidents caused by complex. For leakage monk ditch and LiuGuGou group, based on typical well well Su76-2-3H well leakage occurred after analysis and its process, depending on the degree of leakage, recommends to plugging in different ways, including using control drilling fluid density while drilling plugging, static composite cement plugging and plugging. In order to prevent lost circulation in monk ditch and LiuGuGou group, put forward corresponding preventive measures.Shi qian feng group, and the Shi he zi group set of areas in a horizontal well deflection, inclined and horizontal section. By both geological cause and the borehole trajectory design, easily happened in the sections of borehole wall instability phenomenon. Due to borehole wall instability and the hole is not clean slacking off delimit eye, even serious sticking lead to collapse and sticking sand bridge. Shi qian feng group, and the Shi he zi group for slacking off delimit eye sticking or even collapse,Su19-99H Wells of the former Soviet union are introduced in the stage due to wellbore instability, borehole collapse, caused by lead to hole reaming difficult, caused a huge time and economic loss, has carried on the reason analysis. This article through to the deflecting Angle gain period of borehole wall instability mechanism analysis, carries on the borehole wall stability study, the borehole trajectory optimization was put forward; To optimize drilling fluid system, determine reasonable drilling fluid density; Optimal bit and improving drilling rate, reduce the mud shale soaking time; Drilling equipment equipped with targeted measures, effectively avoided due to the stone feng group and stone box whipstock drilling borehole wall instability problems, greatly improving the mechanical drilling rate, shorten the drilling cycle.For hole cleaning problem of the horizontal well, on the basis of summarizing the predecessors’research at home and abroad, this paper on the influence factors of horizontal well borehole purification geological and physicochemical and engineering aspects of in-depth analysis. Analysis from the aspects of mechanism of drilling horizontal well production of cuttings, settlement and migration, sidewall instability prevention and drilling fluid with rock horizontal well borehole purification method of synergy; By Sue the Su76-4-8H Wells on the basis of field application, in view of the region in a field application of horizontal well drilling hole cleaning countermeasures are put forward measures and solutions, drilling to guarantee measures are put forward, and sums up the different interval in mud with reference to performance. Reduce debris sedimentation from craft, destroy the cuttings bed, horizontal well borehole purification, so as to prevent the happening of the complex and accident.To Sue the drilling tool in areas prone to accidents, this paper made specific analysis the cause of the accident, and provides several common fishing tools in the region of the scope of application and use of the matters needing attention. According to the characteristics of regional strata in drilling in the region are summarized, and some measures of preventing downhole accidents.