OREANDA-NEWS. September 22, 2011. China Oilfield Services Limited  recently successfully applied multilevel pulse perforation in the operation at Well BB5 of Pinghu Oil & Gas Field in China East Sea for the first time. This is a new perforation technology following the Company’s successful application of the jacket-type composite perforator in the operation at Well BB5 of Pinghu Oil & Gas Field, reported the press-centre of COSL.

Multilevel pulse perforation adopts multi stage gunpowder packing technology. Through adjusting the proportion of different kinds of gunpowder, the detonation in the perforator, the gunpowder combustion inside the barrel and the fracturing combustion of gunpowder shaft that sat below will play their role successively based on the different burning speeds of gunpowder.

This technology is able to spread the pressure peaks effectively, to reduce the destructive effects on perforator and borehole from the explosion, as well as to ensure the establishment of a multiple-pressure pulse environment. During the perforating process, the pressure pulses will be amplified within the perforation tunnels, generating micro-fractures in the compacted belt that serve as an extension to interact with the micro-fractures in reservoir, thus enhanced permeability of the percolation as well as the production capacity of oil and gas wells. 

This is the first time COSL implemented multilevel pulse perforation. The operation was done at horizontal well borehole, which is at high temperature with high pressure well. After onsite examination, the rates for the perforating charge shot, blind via correction and gunpowder burn-off all reached 100%.