A Study On Whole-process UBD Technology In Shenbei Buried Hill

Shenbei buried hill region, as the liaohe oil field exploitation of many years old piece, complex formation structure.With the constantly development, reservoir pressure reducing year by year, in reservoir protection, optimal fast drilling safety brought greater difficulty for site construction.Conventional underbalanced drilling in the north shen buried hill region has been preliminary application, the conventional underbalanced drilling is inevitable in the process of tripping mud pollution of oil and gas layer, cause reservoir damage is still serious.To achieve maximum protect reservoirs from mud pollution, this paper analyzes the geological characteristics of buried hill north region, shen for its combined with its characteristics of low pressure, low permeability, reservoir protection and the need of hongxing area, put forward the whole process of underbalanced drilling technology to solve the problem of reservoir damage.In view of the whole process of underbalanced drilling technology at home and abroad research situation and the actual application, comparative forced tripping process and gel technology advantages and disadvantages, combined with shen north buried hill associated gas geological characteristics, optimizing casing valve technology to realize the whole process of underbalanced drilling.Developed the whole process of underbalance key tool sleeve valve, from the main body design to key seal design, combining with laboratory performance test, the tool can meet the needs of drilling operation.Developed low density drilling fluid system, respectively to formate solid free drilling fluid system, the oil- in-water drilling fluid system and hollow glass bead composite drilling fluid system formulation and performance test, combined with the actual needs, targeted optimizing the slurry system.Will be developed at the sleeve valve with low density drilling fluid system for field test in shen north buried hill regio n, underbalanced technology in the whole process is verified the feasibility of shen north.In this paper, through the sleeve valve and the low density drilling fluid system, reasonable solution to shen north buried hill drilling difficulties, the whole process for looking for oil development in old revolutionary speed provides a new way.