Downhole Operation Status Of Workover Technology And Optimization Of New Process

In the course of workover,we often encounter some unknown type and damaged bridge-plugs. We have a difficulty in fishing them out in the absence of special fishing tools or tools uncertain. Meanwhile,during workover operations for oil and gas wells,when fishing out these cracked oil-pipes,conventional fishing method is to first milling the top fish to regular shape, and then take inside or outside the fishing means to fish them out, complicated construction process, schedule more long, seriously affected the production of oil and gas. According to workover situation in Shenyang oilfield, this paper conducted many studies on optimization of the workover tools, downhole fishing tools design against cracked oil-pipes, fully integrated with the spear fishing and box tap technology, full use of slip insert of kava spear fishing as inner cone, while the use of high strength, high toughness, and made thread easy as the advantages of box tap as outside the fishing tools and integration tools through the body to set up a piston cylinder device to pitch ball downside pressure to work within the cone fishing; the bridge plug set of integrated tools for milling and fishing design, make full use of slip insert of kava spear fishing in the spring, driven down as a force within the fishing tool, along with use of high strength, high toughness, and made thread easy as the advantages of box tap as a foreign fishing tools, installed sets of milling head tube in box tap as milling tools,so developed downhole fishing tools against cracked oil-pipes and bridge-plug by using technology optimization principle. It realized integration of the construction work and resolved the fishing problem about cracked oil-pipes and unknown type and damaged bridge-plug in the wells. After field testing and application, their structures, fishing principles and applications, the fishing tools are fully able to meet the downhole cracked oil-pipes and unknown type and damaged bridge-plug construction fishing operations, and have good application value.