Slickline-Deployed Electro-Mechanical Intervention System, a Cost-Effective Alternative to Traditional Cased-Hole Services

Abstract

Abstract During the '90s, the introduction of battery powered electro-mechanical intervention tools increased the versatility of slickline service and changed its image from a simple method that performed mechanical workovers to a complex service technology that could provide safe, cost-efficient alternatives for:locating downhole tubular goods/profilesproducing quality logs from downhole memory surveys at half the cost of traditional servicesaccurate depth measurement for support of all new completion technologiessetting packers without explosivesperforating or cutting tubing or casing. Slickline has again expanded its capabilities. In addition to its proven performance for well remediation, maintenance, and pressure control applications, the new enhancements to the self-powered slickline tools can now be used to perform diagnostic and conformance control functions requiring memory production logging. Applications that require electrical initiation or mechanical manipulation at the tool interface can now be performed with slickline and battery power, insulating the tools from the surface equipment. Mechanical signals transmitted through the wire control the tool start and stop functions and provide real time position telemetry. As a result of the advances in service tools, slickline has increased the scope of its services without a compromise to operational safety and job efficiency and offers the most cost efficient services in well workovers. The case histories will describe how the electro-mechanical intervention tools provide a cost-effective alternative to traditional cased-hole logging systems for many applications as well as many operations that traditionally had to be performed by other service options. History of Service and Equipment Development Traditionally, slickline servicing has been able to provide an effective means for performing well maintenance by high speed mechanical deployment, manipulation, and retrieval of downhole service tools in all types of wells, including those with high pressure and flowing well conditions. Its portability has allowed it to be cost efficient for performing these services in remote locations and on satellite platforms. The introduction of electro-mechanical intervention tools combined with accurate surface measuring instruments has significantly changed the slickline operating envelope. The slickline tools that make the new services possible includes the following:1An electronic measurement system (AMS) that automatically corrects measurement inaccuracies resulting from line stretch and environmental stress factors. 2An electronic triggering device (ETD) that enables safe detonation of explosive devices.A battery-operated, electro-mechanical tool that sets wellbore devices on slickline and braided line without pyrotechnic devices. 3,4A slickline collar locator (SLCL) that accurately verifies collar locations in a tubing string.Data/job loggers (or acquisition software systems) that connect to the electronic measurement system to graphically record dynamic wireline information. While each of the above tools has been instrumental in its own right for the increase of slickline usage, the most significant factor in the increased capabilities of slickline for low-cost intervention has been the methodology that unites the individual tools into systems that can increase job efficiency. Fig. 1 shows a typical slickline service unit and the equipment that can be used in combination to enhance the service capabilities. The tools represented in this figure are discussed in the next sections.