OREANDA-NEWS. April 22, 2013. Professionals of TatNIPIneft have developed an installation for dual production in the small diameter wells. The unit is designed for dual operation of targets (layers) in the wells with a nominal wellbore diameter of 114 mm production casing. Dual production technology was earlier applied in wells with 146 and 168 mm production strings.

The need for a single-lift dual production is due to the fact that technologies of drilling small diameter wells are being the successfully implemented at JSC TATNEFT. 235 wells of this kind have been drilled in the Company as of the beginning of the year. There are multiple productive formations in many of them for each formation.

The unit has been designed for dual production of two packer separated targets (layers) with their optimal operating parameters, and provides for zonal isolation, lifting and allocation metering, as well as the achievement of design development rates.

Besides, as in case of the conventional single-lift installation, when the bottom-hole pressure of the upper target is higher than the pressure of the lower one, the products from the target with the lower bottom hole pressure enter the pump cylinder through the main pump suction valve, and the ones from the upper target - through the additional valve set below the pump cylinder.

If the bottom-hole pressure at the pump is higher at the lower target level, then, the additional valve installed below the pump is connected to the under-the-packer area, while the main valve opening is connected to the annulus.

The first installation the small diameter wells was introduced in mid-December of 2012 at NGDU "Yamashneft". Pilot testing such installations is now planned for six wells of three Company's Oil and Gas Production Boards.