Research on Firing Methods of Full Bore Perforation

摘要

Full bore perforation technology is a mature completion method which is used to explore oil and gas recent years by many companies. This new technology is developed based on the conventional tubing conveyed perforating technique. Work-o-ver string won't be run in and pulled out of hole many times by applying this technique, and the key point of such method is to avoid block-up in the perforating string after perforation. One of the important factors about the full bore perforation is whether an effective path can be created in the string after firing detonating device of perforation. Pressure rating and sealing of detonating devices should be qualified before firing, and a valid path can be opened after firing. There are two detonating methods including impact type and pressure type. Impact detonation device is initialized by dropping bar to impact shear pin, then fire the detonator to crumb the sealing mandrel, and full bore is realized. But firing by the impact method the drop bar and debris of mandrel are compressed and buckled at the under-gauged points, effective full bore can't be created exactly. While pressure detonating device is ignited by pressurizing at the well head to shear pin and fire detonator, sealing mandrel is destroyed to realize full bore. After firing the pressure full bore detonating device larger fragments will be left and the bore is plugged. So the device should be manufactured premise and operated complex, application of this technology can not be widely used, it is the bottle neck of this technique. A new type of full bore detonating device should be researched with such advantages as easy operated, stably detonated, control pressure accurately and little crumb particles of mandrel. In this paper detailed solving proposal is presented according to the problem of firing methods. And results of tests are analyzed carefully; practical application indicates that this new detonating device can be used to satisfy the requirements of full bore perforation technology.