The provision of industry with fuel and power raw materials by rising of output of oil and gas is one of the main economical problems of Ukraine. The National Program "Oil & Gas of Ukraine to 2010" and "State Program of development of output of oil and gas in Ukrainian shelf of Azov and Black Seas" stipulate the considerable rise in the amount and rate of erection of oil and gas wells with their optimal cost and ecology safety. The main factor is operating effectiveness of oil and gas equipment and tools, which work under conditions with considerable static and dynamic stress, with great changing of pressure and temperature in aggressive environment.
The most effective methods which guarantee capacity for work of oil & gas equipment and tools are systematic nondestructive testing and technical diagnostics of their working state. Besides, the nondestructive methods allow to detect available defects and appreciate the working state of equipment and tools for all their working cycle and forecast working state during operating.
The conducted by different experts analysis of accident rate showed that quantity of failures of oil and gas equipment and tools, especially of pipes, is very considerable (20% of pipes (even new) are scarping) and tends to rising.
The reasons of this states are:
- impossibility of enterprises to renew their stock of equipment and tools owing to economic difficulties;
- poor quality of home-produced equipment and tools;
- lack of effective technical means and technologies of nondestructive testing and technical diagnostics;
- poor application effectiveness of available nondestructive testing means.
National Committee of Oil and Gas of Ukraine attaches great importance to guarantee operating of oil and gas equipment without accidents and therefore assigned a mission of working out, manufacture and adoption in industry of different technical means and technologies of nondestructive testing and technical diagnostics of oil and gas equipment to Research & Production Company "ZOND". Now RPC "ZOND" which has considerable scientific, technical and industrial potential works on technical and methodics problems in testing and training and certification the experts in flaw detection.
In conformity with the orders of National Committee of Oil & Gas of Ukraine scientific and technical program "Manufacture, mastering the mass production and adoption in industry of technical means and technologies of nondestructive testing and technical diagnostics of drill pipe strings, drilling and oil mine equipment during mining of oil deposits on land and sea, training necessary specialists. The main aim of this program is intensification, rapid adoptions in industry and effective application of specialized means and nondestructive testing technologies and technical diagnostics of the elements of drilling, causing and tubing string pipes and drilling equipment directly on the site on land and sea.
The offered program stipulates not only provision the branch with technical testing means of oil and gas equipment but working on whole problems complex of organizing, methodical and trained security.
Analyses state of adoption in drilling enterprises of Ukraine the nondestructive testing means showed the following:
Technical provision
Flaw detection services function at the most oil & gas production enterprises in Ukraine. They provided with movable detection flaw laboratories (PLNK) and with portable installations (ZOND). Equipment of these is in these means make it possible to test drilling equipment and tools:
- flaw detection of threaded joints of all drilling pipes types. This testing makes it possible to detect exploitation and works defects and corrosion and fatigue cracks;
- flaw detection of smooth parts pipes and equipment. This testing makes it possible to detect cross- and length-orientated defects;
- wall thickness testing of drilling pipes and equipment.
Application of these means made it possible to decrease (from 60% to 18%) accident rate with drilling tubes, which connected with arising fatigue cracks and breakage threaded joints.
In principle, these failures are the results of organizing mistakes. The reasons of these failures are poor rate of flaw detection specialists and unsatisfactory organization of tools and equipment inspection.
Carried out at last years failures analysis of drilling strings used in drilling, fastening and exploitation, showed that the main reason of accidents which drilling pipes was poor effectiveness of threaded joints by losing their hermetic and strength. This fact sets the specialists, which work out and improve the constructions of drilling pipes, the task of working out new constructions of threaded joints with increased demands to their hermetic and strength. Therefore problem of creating new testing means is very actually now.
The main parameters characterizing the strength of steel drill pipes are grades and yield strength. Reliable determination of these parameters are extremely important in configaration drill pipe strings of exploitated pipes. With the purpose of sorting drilling pipes the series of devices "SIGMA" was created which ensure reliable testing of grades and yield strength of steel drill pipes.
Thus, for technical security is necessary following:
- to provide all nondestructive testing services by complete set of specialized technical means;
- to promote these services at appropriate organizations to realize different kinds of testing.
Technique provision
The quality of nondestructive testing is different to a great instant at various enterprises. The main reason of such state is lack of general methodical decision in nondestructive testing of oil & gas pipes. Now National Committee of Oil and Gas (Derzhnaftogasprom) placed a duty on RPC "ZOND" and some other firms to carry out the general techniques and technical instruction.
This instruction determines the following:
- sorting criteria of every testing object;
- testing means and methods;
- testing methodology;
- identification methods of tested objects;
- flaw detection specialists actions in official registration of testing results;
- standards in testing staff qualification.
The high appreciation of testing quality may be given in case of accurately keeping the rules of this instruction.
Personnel provision
Only qualified flaw detection specialists work at nondestructive testing services. In Ukraine in conformity with International Certification System of nondestructive testing must be all branch specialists recertified in National Certification Centre (NCC) in E.Paton Electric Welding Institute.
Flaw detection specialists must be certified (or recertified) in certificate centre which was organized by NCC at RPC "ZOND" (Ivano-Frankivsk) - the main organization in Derzhnaftogasprom of Ukraine in working out, manufacturing and introduction of technical means and technologies in nondestructive testing and technical diagnostics of oil and gas equipment and tools.Therefore the decision of rising of operating term and operating effectiveness of drilling tubes and oil & gas equipment by means of nondestructive testing demands the improvement of technical, techniques and personnel provision in nondestructive testing services.
In Ukraine there is considerable scientific potential, great know-how and necessary material resources. To eliminate subjective factors in nondestructive testing is necessary to organize the regardless of enterprises services, which must be provided with modern nondestructive testing means and technologies and certified specialists.
