Modulating downhole cuttings via a pulsed jet for efficient drilling-tool development and field testing

摘要

The method of pulsed-jet assisted rock-breaking using cuttings, which combines the advantages of a pulsed jet and an abrasive jet simultaneously, is an emerging drilling technology and can further improve the rate of penetration. Several key techniques of this method are discussed in this paper, including the structure and principle of the modulating tool, the modulation mechanism and the optimization method of the cuttings pulsed jet. An engineering prototype is developed based on the above research works and site conditions. Laboratory tests and field tests of the prototype are successively performed. The application effect is compared with actual drilling data of adjacent wells in the same formation and interval. The results are a good reference for the subsequent drilling. (C) 2015 Elsevier B.V. All rights reserved.