Workover and Completion Technology - A Survey

Abstract

There's gold in them thar workovers, pardner-so let's see how to get it out. By participating in a survey, a representative group of engineers has brought us up to date on the subject and has done some "If only we could..... or had..... or knew how to ". . . to push us into the future. Introduction When costs represented by the annual workover forecast become comparable with the drilling budget, and when a rig-time analysis discloses that completion operations are costing as much as drilling operations, economics, as always, rears its head. In company after company, more manpower is being diverted toward workovers, with the result varying from a few transferred people to major company reorganization. Some companies are reporting 30 percent or higher increases in workover activity, sometimes in a single year. Workover and completion operations more and more are being accomplished by a separate so of "experts" rather than being tacked on to the responsibilities of a drilling or production group. Service companies, expecting a lull in their activity as a result of the declining volume of drilling, are pleasantly surprised to find their business volume pleasantly surprised to find their business volume stable, and sometimes rising, because of the increasing number of workovers. Many of these workovers are appearing in the normal course of events with time and production, just as workovers always have. Many more result from the increasing age of wells and, more important, from higher demand that makes profitable many jobs that were marginal 5 to 10 years ago. With these facts of life and economics goes the hustle that has been added to this phase of our operations. Declining production and lack of drilling opportunities make managers look harder for prospective workover ventures. The increase is offshore as well as onshore, in upper zones as well as lower, and in good wells as well as poor. The subtler "pimples" on logs are being investigated, more stimulation attempts are being made, and more expensive and high-risk workovers are being attempted. Where, then, is workover and completion technology at this time of changing emphasis? It is very much in a state of flux, and few specific ideas are accepted and practiced universally. The technology being used is not practiced universally. The technology being used is not fully documented and reported. The activity is growing at a rate that places technical staffs almost continuously in the role of fire-fighters, without the time and manpower for deliberate study. Far too often it does not permit even a cursory follow-up on results and probable permit even a cursory follow-up on results and probable causes of failure or overexpenditure. For an engineer to take the time to write a technical paper under such circumstances has been out of the question. With this in mind, I have tried to get art idea of what is current in this area of technology. To reach a cross-section of big producers, independents, consultants, contractors, and service companies, I have interviewed about 20 individuals in key spots of workover and completion responsibility and sent out about 80 questionnaires. The questions asked were: What are you doing now? What are you trying that's new? What do you need the most? What are the trends for the next 5 years? JPT P. 1375