Prediction of the propagation of crack-like defects in profile elements of the boom of stack discharge conveyor

Authors

DOI:

https://doi.org/10.15587/1729-4061.2016.85502

Keywords:

boom of stack discharge conveyor, profile element, crack-like defect, resistance to crack propagation

Abstract

The criteria of evaluation of technical condition of structures with crack-like defects on the basis of the concept of «resistance of structural element to crack propagation» were proposed. This indicator is a characteristic of the rate of change in stress intensity factor at the top of the crack in the structure element in the course of its development.

For six model cases of crack-like defects, taking into account the theoretical principles of mechanics of destruction of materials and structures, we established analytical dependences of SIF KI and derivative dKI /da with respect to dimensionless parameter a/t, where a and t are characteristic dimensions of a crack and a slab. We substantiated the characteristic values of ratios (a/t)*, as well as the depth of potential crack-like defects, in case of exceeding of which there is an abrupt increase in the rate of change in stress intensity factor KI. Values (a/t)* will be used for assessing the strength and reliability of elements of constructions with crack-like defects.

At the same time, using the created experimental database and analytical relationship in the form of the Paris power law, the criterial values of SIF in the studied elements of structures for different systems «material-environment» were defined. These values are put into the basis of calculating critical lengths of crack-like defects in profile elements of the structure by the model scheme, considered above.

The examples of assessing technical condition of damaged elements of a structure according to the cracks depth with regard to operational factors (load nature, influence of working media, condition of material etc.) were considered. Engineering recommendations for the prediction of crack-like defects were formulated.

As an analysis of the outcomes of conducted studies demonstrated, monitoring of defect detection of profile elements of the boom of stack discharge conveyor is necessary to carry out, guided by the calculations of resistance of material to crack propagation. Each system «material – environment» requires an individual approach to diagnosis and monitoring of technical condition.

The research outcomes might be used for engineering evaluations of the results of monitoring of profile elements of the boom of stack discharge conveyor.

Author Biographies

Leonid Polishchuk, Vinnytsia national technical university Khmelnytske highway, 95, Vinnytsia, Ukraine, 21021

PhD, Professor

Department of machine tools and automated production equipment

Orest Bilyy, National university «Lviv polytechnic» S. Bandery str., 12, Lviv, Ukraine, 79013

PhD

Department of Strength of Materials

Yevhen Kharchenko, National university «Lviv polytechnic» S. Bandery str., 12, Lviv, Ukraine, 79013

Doctor of Technical Sciences, Professor

Department of Strength of Materials

References

  1. Dmytrakh, I. M., Vainman, A. B., Stashchuk, M. H. (2005). Mekhanika ruinuvannia i mitsnist materialiv. Akademperiodyka Publ., 378.
  2. Dmytrakh, I. M., Panasiuk, V. V. (1999). Vplyv koroziinykh seredovyshch na lokalne ruinuvannia metaliv bilia kontsentratoriv napruzhen. Fiz.-mekh. in-t im. H. V. Karpenka Publ., 341.
  3. Polishchuk, L., Bilyy, O., Kharchenko, Y. (2015). Life time assessment of clamp-forming machine boom durability. Diagnostyka, 16 (4), 71–76.
  4. Paton, B. Ye. (Ed.) (2009). Tsilova kompleksna prohrama naukovykh doslidzhen NAN Ukrainy “Problemy resursu i bezpeky ekspluatatsii konstruktsii, sporud ta mashyn”. In-t elektrozvariuvannia im. Ye. O. Patona, 709.
  5. Polishchuk, L. K., Kharchenko, H. V., Zvirko, О. І. (2015). Corrosion-Fatigue Crack-Growth Resistance of Steel of the Boom of a Clamp-Forming Machine. Materials Science, 51 (2), 229–234. doi: 10.1007/s11003-015-9834-8
  6. Kharchenko, E. V., Polishchuk, L. K., Zvirko, O. I. (2014). Estimation of the In-service Degradation of Steel Shapes for the Boom of a Clamp-Forming Machine. Materials Science, 49 (4), 501–507. doi: 10.1007/s11003-014-9642-6
  7. Dmytrakh, I. M., Tot, L., Bilyi, O. L.; Panasiuk, V. V. (Ed.) (2012). Mekhanika ruinuvannia i mitsnist materialiv Dovidn. Vol. 13: Pratsezdatnist materialiv i elementiv konstruktsii z hostrokintsevymy kontsentratoramy napruzhen. Spolom Publ., 316.
  8. Toth, L., Rossmanith, P. (1999). Brief History of Fracture Mechanics and Material Testing. Miscolz, 163.
  9. Tóth, L. (1994). Reliability assessment of cracked structural elements under cyclic loading. Handbook of Fatigue Crack Propagation in Metallic Structures, 1643–1683. doi: 10.1016/b978-0-444-81645-0.50024-x
  10. Toth, L.; Aliabadi, М. Н., Brebbia, C. A., Carlwright, D. J. (Eds.) (1990). A computer aided assessment system of reliability cyclic loaded construction elements having flaws. Computer-Aided Assessment and Control of Localized Damage, 39–53.
  11. Toth, L. (1981). Describing the fatigue crack growth circumstances by damage process. GEP., 257 – 262.
  12. Toth, L. (2001). Crack propagation sensitivity index as the tool to promote the fracture mechanics concepts. Fiz.-khim. mekhanika materialiv, 2, 63–68.
  13. Zhang, W., Pommier, S., Curtit, F., Léopold, G., Courtin, S. (2014). Mode I Crack Propagation under High Cyclic Loading in 316L Stainless Steel. Procedia Materials Science, 3, 1197–1203. doi: 10.1016/j.mspro.2014.06.195
  14. Fremy, F., Pommier, S., Galenne, E., Courtin, S. (2012). A scaling approach to model history effects in fatigue crack growth under mixed mode I+II+III loading conditions for a 316L stainless steel. International Journal of Fatigue, 42, 207–216. doi: 10.1016/j.ijfatigue.2011.10.013
  15. Wang, B. L., Wang, K. F. (2013). Effect of surface residual stress on the fracture of double cantilever beam fracture toughness specimen. Journal of Applied Physics, 113 (15), 153502. doi: 10.1063/1.4801875
  16. Pluvinage, G., Capelle, J., Hadj Méliani, M. (2014). A review of fracture toughness transferability with constraint and stress gradient. Fatigue & Fracture of Engineering Materials & Structures, 37 (11), 1165–1185. doi: 10.1111/ffe.12232
  17. Jin, Z., Wang, X. (2013). Weight functions for the determination of stress intensity factor and T-stress for semi-elliptical cracks in finite thickness plate. Fatigue & Fracture of Engineering Materials & Structures, 36 (10), 1051–1066. doi: 10.1111/ffe.12070
  18. Tada, H., Paris, P. C., Irwin, G. R. (1973). The Stress Analysis of Cracks Handbook. Del Research Corporation (Hellertown), 677.
  19. Merkblatt DVS 2401 (2004). Bruchmechanische Bewertung von Fehlern in Schweißverbindungen. Deutscher Verband für Schweißtechnik. 271.
  20. Newman, J., Raju, I. (1983). Stress-Intensity Factor Equations for Cracks in Three-Dimensional Finite Bodies. Fracture Mechanics: Fourteenth Symposium – Volume I: Theory and Analysis, I–238–I–238–28. doi: 10.1520/stp37074s
  21. Paris, P., Erdogan, F. (1963). Closure to “Discussions of ‘A Critical Analysis of Crack Propagation Laws’” (1963, ASME J. Basic Eng., 85, pp. 533–534). Journal of Basic Engineering, 85 (4), 534. doi: 10.1115/1.3656903
  22. Panasyuk, V. V., Dmytrakh, I. M., Toth, L., Bilyi, O. L., Syrotyuk, A. M. (2014). A Method for the Assessment of the Serviceability and Fracture Hazard for Structural Elements with Cracklike Defects. Materials Science, 49 (5), 565–576. doi: 10.1007/s11003-014-9650-6

Downloads

Published

2016-12-26

How to Cite

Polishchuk, L., Bilyy, O., & Kharchenko, Y. (2016). Prediction of the propagation of crack-like defects in profile elements of the boom of stack discharge conveyor. Eastern-European Journal of Enterprise Technologies, 6(1 (84), 44–52. https://doi.org/10.15587/1729-4061.2016.85502

Issue

Section

Engineering technological systems