The Paton Welding Journal, 2014, №06



2014 №06 (04)

DOI of Article 10.15407/tpwj2014.06.05

2014 №06 (06)

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The Paton Welding Journal, 2014, #6-7, 29-30 pages  

PECULIARITIES OF DEGRADATION OF METAL OF WELDED JOINTS OF STEAM PIPELINES OF HEAT POWER PLANTS

V.V. DMITRIK and S.N. BARTASH

NationalTechnicalUniversity «Kharkov Polytechnic Institute». 21 Frunze Str., 61002, Kharkov, Ukraine. E-mail: svarka126@ukr.net
 
 
Abstract
The peculiarities of degradation of structure and damageability of metal of welded joints of the steam pipelines of heat power plants of long-term operation period (more than 250,000 h) under the conditions of creep and low-cyclic fatigue are given. It is shown that welded joints of steels 15Kh1M1F and 12Kh1MF are damaged mostly along the areas of fusion, overheating and partial recrystallization of metal in the near-weld zone and also in the places of joining pipe elements of different thicknesses. 13 Ref., 1 Table.
 
 
Keywords: welded joints of steam pipelines, degradation, structure, creep cracks, fatigue cracks, carbides
 
 
Received:                20.05.14
Published:               28.09.14
 
 
References
1. Antikajn, P.A. (2001) Metals and strength design of boilers and pipelines. Moscow: Energoservis.
2. Khromchenko, F.A. (1992) Service life of welded joints of steam pipelines. Moscow: Mashinostroenie.
3. Dmitrik, V.V. (2013) Welded joints of steam pipelines. Kharkov: Majdan.
4. Dmitrik, V.V., Tsaryuk, A.K., Bugaets, A.A. et al. (2006) Evaluation of remaining life of welded joints of pipelines for thermal power plants. The Paton Welding J., 2, 6-10.
5. Dmitrik, V.V. (2004) To creep of welded joints from low-alloy Cr-Mo-V heat-resistant pearlitic steels. Vost.-Evrop. Zhurnal Pered. Tekhnologij, 6, 88-92.
6. RD 135-34. 1-003-01 (RTM-1s): Welding, heat treatment and control of pipe systems of boilers and pipelines in mounting and repair of power equipment. Moscow: NPO OBT.
7. Anokhov, A.E., Alekseeva, I.A. (1982) Accumulation of damages in welded joints of steam pipelines from 12Kh1MF steel during creep process. Svarochn. Proizvodstvo, 9, 34-35.
8. Khromchenko, F.A. (2001) Reliability of welded joints of pipes, boilers and steam pipelines. Moscow: Energoizdat.
9. Berezina, T.G., Borodina, E.R., Ashikhmina, L.A. et al. (1974) Fine structure of heat affected zone in welding of 15Kh1M1F steel. Avtomatich. Svarka, 12, 19-22.
10. Khromchenko, F.A., Kalugin, R.I., Lappa, V.A. et al. (1999) Peculiarities of structural changes in welded joints of 15Kh1M1F steel during creep. Svarochn. Proizvodstvo, 10, 12-15.
11. MU34-70-161-87: Technical recommendations on metallographic analysis in evaluation of quality and investigation of damage causes of steam pipeline welded joints of 12Kh1MF and 15Kh1M1F steels for heat power plants. Moscow: F.E. Dzerzhinsky VTI.
12. RD 34.17.421-92: Type instruction on control and service life prolongation of metal of boiler base elements, turbines and pipelines of heat power plants. Moscow: ORGRES Service of best practice.
13. Dmitrik, V.V., Shelepov, I.G. (2005) To evaluation of remaining life of welded joints of heat power plant pipelines on structural factors. Energetika i Elektrifikatsiya, 9, 41-43.