No abstract

No abstract

No abstract

Achimov deposits extend over 12,000 square kilometers around the city of Novy Urengoy. These deposits are characterized by high reservoir pressures, and a narrow range of drilling fluid densities that creates complicated conditions for drilling and completion of wells. Due to the high accident rate of drilling horizontal wells only S-shape wells were drilled for this formation. The first successful horizontal production well was drilled in 2013 in cooperation Arcticgaz, ERIELL, Schlumberger. The first well to drill a horizontal wellbore on Achimov formation, has been planned to open Ach3,4 and Ach5 layers of Achimov formation. In close cooperation with project operator - Arcticgaz company, engineering group of Schlumberger drilling contractor and drilling contractor developed and successfully implemented comprehensive solutions for drilling and completion of horizontal wells Achim. One of the key factors of success was the use of drilling muds Megadril-D with constant control of equivalent circulating density. Application of rotary steareable system with optimally balanced PDC bits, allowed to drill horizontal wells through Achimov deposits in record time. An additional factor for drilling risks reduction was implementation of geomechanic model, as in the preparation of the preliminary model and real-time control for wellbore stability with the latest technology logging measurements (LWD) – acoustic and density neutron formation properties. In the period for 2013 to the 2nd quarter of 2014 have been successfully constructed more than 10 similar wells. Esteblished new records: maximum closure – 2403 meters, the length of the longest subhorizontal section reached 1233 meters. Set a record duration of well construction time of 62 days vs 100 planned, which could not been reached before by anyone in the region (formerly similar wells with shorter intervals of subhorizontal sectionhave been constructed in evarage about 150 days). Recently were successfully run two completion liners for 3-stage hydraulic fracturing (MSF) and one of MSF was successfully done. For completion purposes was used OBM with the weighting agent of mikro size, provided an unprecedented stability to settlement for a long time. This article devoted to the description of technologies and solutions that have been used for the construction of sub-horizontal wells. Preliminary production index of subhorizontal wells shows that current PI higher than S-shape wells (even with frac). Positive experience in the construction of subhorizontal wells change plans to develop Achimov deposits and opens new perspectives of hydrocarbon production in the region.

Power circuit arrangements of independently excited reactive electric drives are presented. It is shown that the number of switches is determined by the number of phases and lies in the range from 2f to 4f. It has been ascertained by regression analysis that the unit price of semiconductor converters at minor current values does not depend on current and is determined by the cost of the microprocessor control system. At cur rents >100 A, the price-current relation is nearly linear and the rejection of three phase power circuits of semiconductor converters in favor of multiphase power circuits does not therefore increase power supply weight and size. Thus, the more complex configuration of power circuit arrangements (increased number of phases) for processing plants with an installed capacity of more than 200 kW can improve the weight and size of the electromechanical converter while maintaining the size of the semiconductor converter.