Ezequiel Fernandez
Tenaris
The current reservoirs declination and depressurization in combination with the continuous reduction of incorporated reserves to the oilfields has challenged the engineer staff to either increase the extraction rate, with a significant increase of the water volumes applied in order to pressurize the field and/or pushing the limits of the artificial lift system (ALS) using biggier pumps and equipment in combination with deeper wells. Despite all the safety factors that have been considered for conventional sucker rod designs, the operating companies understood that the system was reaching its mechanical limit due to frequent and premature failures. After analyzing records, field data basses and statistics we concluded the API sucker rod connection is the weakest link of the system, where around 75% of failures occur. To face this mechanical limitation and to increase the rod pumping efficiency Tenaris developed the premium connection, which overcomes the threshold set by the API connection. Since 2008 to these days this technology was used in different oil fields increasing its performance and making feasible to produce wells with extreme conditions. This paper aim is to show the sum up of the most representative experiences: higher loads, increasing production, reducing failures and extending running life; establishing new parameters in the artificial lift system.