• Low-impact perforation • Combined treatment of wellbottom zones • Making a Wide High-Quality Opening-up Zone • Making a reliable communication with formation • Perforation in horizontal and intensely slanted wells • Safe frac job
Low-impact perforation
Plastisoft™ Perforation does not create impact effect on production casing, which ensures integrity of annular cement column above and below the treatment interval, as well as eliminates behind-casing fluid movement. This feature has ultimate safety, and provides for “surgical” opening of pay zones with poor quality of annular cement column at adjacent water-oil contact areas. It also helps to prevent early cement squeezing operations.
Combined treatment of wellbottom zones
Picture of an appearing cavern, a concrete block being the object.
Through the newly-cut slots in the well production casing the perforator fluid jets at high pressure break down the cement column and adjacent rock making caverns deeper than 1.5 ft which allows to radically improve the filtration properties of the formation wellbore part. The fluid-jet break-down method allows to clean the wellbottom zone from remnants of drilling mud, cement, asphalt and paraffin depositions, other contaminants, thus providing skin factor reduction. Service water, oil, acid compositions, surfactants can be used as fluid for making caverns. Along with forming lengthwise slots and making caverns in the wellbottom area, NEKKO combined perforators enable, in one trip, a comprehensive treatment of bottomhole zone with a followed swabbing of fluid through holes in the upper section of the perforator. Chemical compositions’ injection into the formation can be done both, through the fluid jet nozzles which enables a selective treatment of most problem areas, as well as through additional holes in the upper section of perforator which helps to obtain a reentry-guide-mode treatment of the bottomhole zone.
Making a Wide High-Quality Opening-up Zone
Double lengthwise slots 0.39 to 0.47 in. wide are formed in the well production casing, the open-up square area of one linear foot of casing equals to 72 sq. in. which is adequate to open-up area created by 34 shaped charges with bore ID 1in. An even number of slots (2 – 4 – 6) is formed in a given interval. The slot geometry in the opening-up area allows to involve into production the highest number of fluid-conduction channels and fissures. The total exposed thickness makes up to 90 feet at a run.
Comparison of main parameters of Plastisoft™ Perforation versus jet perforation
Making a reliable communication with formation
Forming double lengthwise slots in the production casing, together with making caverns in the bottomhole zone presents the best known perforating method to facilitate formation communication.
Perforation in horizontal and intensely slanted wells
The entire scope of features of the above method can be applied in horizontal or intensely slanted well bores, as well as in 2-nd wellbores due to a selection of different size perforators.
Safe frac job
A pre-frac execution of this approach due to a stable hydrodynamic communication with the formation enables the following:
• Considerably reduce hydraulic resistance while pumping proppant into the formation. • Prevent any “emergency stops” due to poor quality of perfs during displacing proppant of different fractions. • Better conditions for usage coarse fraction proppant. • Better conditions for high proppant concentrations. • Better conditions for higher velocity of proppant displacement. • Enhance operation in horizontal or intensely slanted wells. • Provide for selective frac-on-squeezing job. • Provide for directional hydraulic fracturing, due to ability to position the formed slots on a given azimuth within the proliferation of formation stresses.
An important advantage of the NEKKO combined Plastisoft™ Perforation is a big volume and depth of appearing caverns, which ensure the efficiency of oil recovery methods appliance.
