Evaluation Of Completion Technology Of Branch Well And Effect Of Increasing Production

Multilateral well completion’s isolation of each branch segment,control and wellbore stability technology becoming mature.Our country in the multilateral well completion have great progress in recent years.Our well completion system is developed with independent intellectual property rights.However,compared with foreign advanced well completion device,most of them are designed for a block oil and gas field,which is lack of general applicability and difficult to large-scale promotion.Our country exists gap with foreign in isolation problem of multilateral well,which is mainly reflected in the completion of downhole device which intelligent degree is not high and poor controllability.This paper study the branch well completion system and tools supporting through to the domestic and foreign,from the branch well completion technology to the evaluation and stimulation,combined with the design and construction of001-Z45well completion,research branch well reentrance technology and the positioning of bulged tube.Through evaluatuing the effect of measures to Hechuan001-Z45well stimulation,we can have the following understanding and conclusion:(1) Multilateral well3-5level completion system is mainly composed of lower the orientation and positioning device,window milling device,sidetrack drilling system,salvage and recovery device,re-entry duiding device,hanging device and supporting tool consisting of different completion methods.(2)The fork position of multilateral well bearing capacity of cement mantle requires develop specific window aquasseal and special cement milk to improve the cementing quality and cement strength.(3) Bulged tube positioning method can provide more big inner diameter,conducive to the conventional completion,stimulation,workover tools used,so it has better adaptability,but also has certain risk.(4) BAKER wall hook suspension system can not only provide the mechanical support of branch hole but also provide reentrant channel for branch hole and branch main.Tere are several reentrant manners with lower risk.(5) Selective reentrace technology in the process of completion and stimulation of001-Z45Hechuan:drilling process,the branch hole re-entry using whipstock re-entry system;completion process,the branch hole selective re-entry using Xinjiang pre-tapping suspension system stimulation process,the branch hole selective re-entry can use bending sub;workover process, the branch hole selective re-entry using probe direction re-entry system.(6)Stimulate and reform of Hechuan001-Z45multilateral well:as longitudinal gas reservoirs of Hechuan Xujiahe has many layers,we should use the separate layer fracturing, the design should meet the need of "increase the slot length,control the high of slot,reduce the damage,accelerate the return flow "the upper part of Xuer has a high construct pressure,we should control the maximum sand concentration to reduce construction risk;take the low pressure of window cutting of multilateral well’s casing into consideration,construction need to control casing pressure;In order to prevent excessive reflux of proppant drain recommend to use these method:control back pressure,progressively larger glib,hard closing.