Russia’s IRZ is adopting an approach widely used in space hardware for its downhole monitoring systems, boosting reliability and service life
For space projects, equipment reliability and service life are crucial, since failure of a single element can cause mission disruption and billions of dollars in losses.
The same applies to artificial lift electronics, where maintenance of a downhole sensor is not possible without ESP stop and pull-out. In most cases, the ESP unit continues operating even when the sensor is down, and reduced production rate causes profit losses, especially in high flow rate wells. Moreover, the risk of ESP failure becomes extremely high.
To mitigate these risks, IRZ implements redundant electronic systems, the approach widely used in space hardware, to provide unrivalled reliability and long service life.
This year the company introduced a new redundant downhole monitoring system for ESP with induction or permanent-magnet motors. The sensor monitors temperature and pressure of reservoir fluid, motor oil or stator winding temperature, motor vibrations, and current leakage and includes a hydraulic control line to monitor discharge pressure. It can be used with motor drives of any vendor, in wells with depth up to 19,500 ft, operating pressure up to 8,800 psi, and temperatures up to +150° C.
High reliability of the new downhole monitoring system is ensured by two standalone electronic modules inside the downhole sensor: the main one being operating, whereas the standby one is off. Should the main module fail, the system can switch over to the standby module, either on the operator’s command or automatically, assuring troublefree operation of the system.
“The new product is meant to reduce economic risks of oil companies and cut costs for round-trip operations. Through the use of full redundancy, we managed to lower failure level of the sensor down to as little as three per cent within three years, even in severe operating conditions,” comments Sergey Feofilaktov, chief designer of IRZ.
In addition, the standby electronic module can be used to verify measurement accuracy of the main module by comparing readings.
The new redundant downhole monitoring system has successfully passed field tests in two oil companies. The first systems installed have been in operation for over 16 months; during this period, the main module was switched over to the standby one only to test the technology.
Highly regarded following the results of field tests, the new product is experiencing strong demand in the market; more than 50 redundant systems have been shipped as of June 2018.
IRZ is one of the first Russian companies to design and launch manufacture of downhole monitoring systems for ESP. The first system was produced in 1998; since then, the company has manufactured and shipped more than 50,000 units. The product range includes dozens of versions of downhole monitoring systems, variable frequency drives / switchboards / soft starters for electric submersible motors, and automated control systems for oil production. The equipment is used by leading oil producing and service companies, such as Lukoil, Rosneft, Surgutneftegas, Tatneft, Bashneft, Slavneft and Gazprom Neft, as well as internationally in countries including Tajikistan, Kazakhstan, Azerbaijan, China, Indonesia, India, Venezuela and South Sudan.
