№ 10 (October 2010)
Premium Production – Advances in Threading Technologies
Premium-class threaded joints ensure a well’s high resistance and complete tightness and help produce oil and gas in environments where traditional technologies cannot be applied. The premium segment of TMK’s activity was established in Russia three years ago and now includes production of pipes with premium threaded joints at the TMK-Premium Service unit’s facilities.
Today the company is expanding its business boundaries: the enhanced quality thread is produced at all TMK plants, including IPSCO’s American pipe-production assets purchased in 2008. Sergei Rekin, Deputy Director General for Research and Development at TMK-Premium Service, told OGE about advantages that helped the company enter the international market and about its new developments.
OGE: Sergei Aleksandrovich, could you tell us about the stages involved in manufacturing premium threaded joints?
Rekin: To begin with, we evaluate the market for what we can offer the consumer. First, we look into import substitution and analyze products supplied by foreign manufacturers. Second, we strive to stay ahead of competition to provide the consumer with competitive solutions. New ideas appear to be later implemented in practice. Afterwards there is a large set of laboratory, bench, and field tests performed both by our own staff at the RosNITI research unit and by other contractors. The new products receive qualification which in essence confirms the consumer’s requirements. Then we arrange and launch serial production at the company’s plants.
OGE: You mentioned staying ahead of competition. Could you give an example?
Rekin: A typical example is the new range of products that will be offered to consumers. These are pipes made of steel containing 5 percent and 13 percent of chrome designed for wells yielding carbon dioxide in the extracted products. Superchrome steel pipes are designed for wells containing H2S in addition to СО2. The products we offer will help Russian consumers to considerably extend the service life of wells in aggressive environments. This is an area of our ongoing work under research and engineering programs in cooperation with Gazprom and Rosneft.
OGE: What tests do consumers usually require for threaded joints?
Rekin: We strive to apply the API 5C5/ISO 13679 standard that is used for tests internationally. This standard ensures quite a tough procedure for threaded joint tests. It includes four evaluation categories, the highest being CAL4, which is mainly required for testing joints designed for operation at offshore fields.
In Russia, Gazprom tests threaded joints for gas tightness at its research unit Gazprom VNIIGAZ. According to its rules, all new threaded joints undergo bench tests at Gazprom VNIIGAZ. The uniqueness of the equipment available there enables field tests of joints in environments containing hydrogen sulphide. It should be pointed out that all premium threads produced by TMK have successfully passed these tests.
OGE: Are your products tested abroad?
Rekin: Yes, they are. For instance, tests for compliance with API 5CT/ISO 13679 are carried out at the Oil States Center in Aberdeen (Scotland) and CNPC Center in China, as there is no similar equipment in Russia yet to date.
OGE: What can you tell us about TMK-Premium Service designers’ latest engineering solutions?
Rekin: Drilling pipes with double-shoulder TMK-TDS joints have been widely used and acknowledged. Gazprom is giving up the regular design and will use only tubing with double-shoulder joints. We have also designed TMK-EXD tool joints, which help optimally use the strength properties of drilling pipes. The EXD tool joints’ design enables using the enhanced internal passage when using pipes of standard strength groups. We plan to develop this range for the horizontal drilling market.
A modification of the ТМК-PF ET threaded joint for casing tubes has been designed to be used in arrangements of wells with long horizontal wellbores. This design makes it possible to apply excessive rotation torque to the joint during the run-in-hole operation. This joint is also positioned for casing pipe drilling.
OGE: You pay a lot of attention to horizontal drilling. Does this mean this type of drilling is developing actively?
Rekin: Yes, that trend certainly exists. Foreign companies with higher requirements for the pipes’ strength are entering the Russian market with their proprietary technologies. The U.S. and Russian drilling schools have been developing side by side, the main difference being the fact that turbine motor drilling has been used in Russia, whereas in the U.S. they used rotary drilling. That’s why the load and requirements for pipes differ considerably.
In rotary drilling the load on the drilling tube casing is several times higher that’s why the drilling pipes’ yield limit exceeds 931 MPa. The Russian drilling market is actively developing, and Western technologies are coming here too. This became evident over the last five years. The drilling pipes market has gone towards the high-strength segment. This results from the use of the so called S-shaped profiles in wells with high-bend and horizontal wellbores, designed by the engineers to obtain the maximum efficiency of the constructed well.
OGE: How has this trend affected TMK’s activities?
Rekin: In 2008 TMK comprised TMK-IPSCO’s American enterprises with their range of ULTRA collarless premium threaded joints. By the way, ULTRA threaded joints make up over 40 percent of the U.S. market of premium joints used in the production of shale gas and the market share is increasing with new non-traditional gasfields.
The cooperation within the company helps provide the customers with the complete range of pipes to build wells of any class of complexity, including horizontal wells: collared and collarless pipes with premium threaded joints of the assortment ranging from 60 to 426 millimeters. The complete supply package of pipes also helps offer a casing design that could reduce the amount of metal, sometimes up to 20-25 percent, and change the concept of traditional well design both in Russia and abroad.
The competitive advantage of TMK-Premium Service is in the fact that the company offers solutions than can help reduce the cost of well drilling, construction and operation by up to 25-30 percent.