Vol. 7 4, 2017 p 54-61


Article name, authors, abstract and keyword


Development of repair components for selective repair of the pipelines

Nikolay G. Goncharov a, Aleksey A. Yushin a, Artem V. Sudnik a

a Pipeline Transport Institute, LLC (Transneft R&D, LLC), 47a, Sevastopolskiy prospect, Moscow, 117186, Russian Federation


Abstract: Introduction. The paper reviews the topical issues of selective repair of defective sections of oil and oil products pipelines with the help of repair components - split and female tees. The analysis of split tees use is provided, the peculiarities of installation and welding works, as well as field research results are stated.
State of the issue. The key element in arrangement of reliability and safety of oil transportation to consumers is timely technical maintenance and repair of the pipelines. Despite of insulation and electrochemical protection of the pipelines, individual sections of long-term operated pipelines have external and internal damages, both corrosive and mechanical, and defects of electric arc welding of girth and longitudinal welds, which are considered hazardous under contemporary quality control standards. Safety of Major Pipelines (MP) operation and their reliable uninterrupted operation are secured by relevant activities both at the design stage and during MP operation. Among operating activities the arrangement of periodical technical diagnostics of MP elements state and elimination of unacceptable defects are of great importance. A considerable part of detected defects is unacceptable and requires elimination. One of the directions of repair technologies development is the development of repair elements which allow to perform the repair both on operating and on shutdown pipeline. A special attention in this connection must be paid to the split tees, which are used in cases when usage of other repair elements or methods is ineffective or impossible.
The challenge. Until quite recently the split tees were used for repair of the pipelines with the diameter 5301220 mm, there were no repair elements for pipes with the diameter 219426 mm. The paper provides technical solutions for repair of the small diameter pipelines.
Testing methods. Here we present the results of static strength and durability testing of repair elements by cyclic loading at maximum allowable loads under operating conditions on specialized stand and detailed testing methods are described.
Testing results. Stand testing have indicated that the tested specimen were not destroyed at loads simulating the maximum pipeline load under operating conditions.
Conclusions. Evaluation of research results has indicated that the service life of the developed repair elements can come up to min. 30 years, which makes it reasonable to use them for repair works execution on small diameter pipelines.

Keywords: split tee, welds, major pipelines, welding, pipe, heat-affected area, thermal cycle of welding, mechanical properties

Reference for citing:
Goncharov N. G., Yushin A.A., Sudnik A.V. Development of repair components for selective repair of the pipelines. Naukatekhnol. truboprov. transp. neftiinefteprod. = Science & Technologies: Oil and Oil Products Pipeline Transportation. 2017; 4(7):5461.

[1] Goncharov N. G., Gobarev L. A., Kolesnikov O. I., Lopatin E. V., Romanova I. A. Repair of line section of the major pipelines with the help of split tees. Pipeline transport: theory and practice. 2010;(4):2830. (In Russ.)
[2] Split tee with the reinforcing branch pipe for pipelines: pat. 114 744 Rus. Federation No. 2011140097(06): appl. 04.10.2011; publ. 10.04.2012. Bull. No. 10. (In Russ.)
[3] Split tee with the reinforcing branch pipe for pipelines: pat. 116 953 Rus. Federation No. 2011141942/06: appl. 18.10.2011; publ. 10.06.2012. Bull. No. 16. (In Russ.)
[4] Method of pipeline welding without preliminary heating of connections: pat. 2 521 920 Rus. Federation No.2013104099(02): appl. 31.01.2013; publ. 10.07.2014. Bull.No. 19. (In Russ.)
[5] But V. S., Velikoivanenko E. A., Oleinik O. I. Peculiarities of split tees usage at repair and modernization of major pipelines under operating conditions. Automatic welding. 2009;(9):3238. (In Russ.)
[6] But V. S., Gretskiy Y. Y., Rozgonyuk V. V. Objectives of the new approach to execution of welding works on pressurized pipeline. Oil and Gas Industry. 2001;(4):3339. (In Russ.)
[7] Mahnenko V. I., et al. Mathematic simulation of through faults in operating oil and gas pipelines and development of numerical numerical procedure for evaluation of allowable modes of arc welding of defects. Automatic welding. 2001;(11):310. (In Russ.)
[8] Yakubek P. Assembling of tees and fittings T. D. Vilyamson on operating pipeline. Paper presented at: Welding and relevant technologies at construction, modernization and repair of gas and oil pipelines; 2007 Nov 2223; Moscow, Russian Federation.
[9] Mahnenko V. I., et al. Determination of allowable sizes of welds at installation of tees and couplings on operating major pipelines. Automatic welding. 2003;(8):712. (In Russ.)
10. Assessment of integrity of structures containing defects / I. Milne, R. A. Ainsworth, A. R. Dowling, A. T. Stewart //CEGB Report R/H/R6, Revision 3, Apr. 1986.
[11] Volmir A. S. Stability of deformable systems. Moscow (M): Science; 1967. (In Russ.)
[12] Shafikov R. R. Experimental justification of major pipelines repair using welding technologies without gas transfer shutdown. Oil and gas territory. 2009;(4):4851. (In Russ.)
[13] Shafikov R. R. Repair of major pipelines using welding and relevant technologies without gas transfer shutdown. Oil and gas territory. 2009;(6):8083. (In Russ.)
[14] Operability of welding couplings for repair of pressurized pipelines defects / A.G. Mazel [and others]. Construction of pipelines. 1996;(1):1622. (In Russ.)
[15] Mazel A. G., Gobarev L. A., Nagornov K. M., Rybakov A. I. Welding couplings for pipelines repair. Gas Industry. 1996; (910):5557. (In Russ.)
[16] Goncharov N. G., Kolesnikov O. I., Yushin A. A., Filippov O. I. Investigation of low ambient temperatures impact on welding technology and properties of major pipelines welds. Science & Technologies of Oil and Oil Products Pipeline Transportation. 2016;(7):5661. (In Russ.)