Objectives, role and methods of damage assessment in quality assurance of sucker rod maintenance and rod string repair

The need for integrated damage rating during damage assessment of sucker rods and evaluation of the conditions of their further application in repair rod strings is analyzed in terms of reliability theory of equipment operations with basic elements connection to solve the problem of implementation of operational-state-based approach to sucker rod and rod string operation. Existing maintenance performance metrics for used sucker rods were examined. The paper provides the rationale for final quality metrics for sucker rod maintenance, necessary to ensure fail-safe operation of sucker rod strings downhole, through transition from failure investigation and examination concept to prediction and prevention. An algorithm for sucker rod damage assessment during maintenance according to operational state and quality standards based on damage rate is substantiated. This should ensure the transition from localized detection of individual faults to an integrated numerical assessment of operational status and damage rate. Implementation of numerical assessment is key to development of an automated database management system of maintenance and repair data for all downhole equipment of sucker rod pumping units through elaboration of managerial decisions to ensure the balance between fail-safe run life downhole and the cost of life cycle of downhole pumping equipment considering the geological state of reserves and fluctuations in market prices of produced fluids in accordance with formally described methods of reliability theory and large-scale maintenance within unified procedures.

References

1. Klimov V.A., Valovskiy K.V., Valovskiy V.M. et al., Reducing the risk of rod breakage with improved methods of qualitative and quantitative assessment of the remaining life (In Rus.), Neftyanoe khozyaystvo = Oil Industry, 2009, No. 7, pp. 60–64.

2. Klimov V.A., Valovskiy K.V., Valovskiy V.M. et al., Improvement of downhole pumping equipment maintenance system (In Rus.), Neftyanoe khozyaystvo = Oil Industry, 2010, No. 7, pp. 52–54.

3. Klimov V.A., Valovskiy K.V., Valovskiy V.M. et al., Justifying diagnostic indicators of pump rod fatigue failure (In Rus.), Neftyanoe khozyaystvo = Oil Industry, 2009,

No. 11, pp. 126–129.

4. Klimov V.A., Valovskiy K.V., Valovskiy V.M. et al., On the physics of failures, methods of reliability calculations, and efficient performance of rod string in a well (In Rus.), Neftyanoe khozyaystvo = Oil Industry, 2011, No. 7, pp. 66–69.

5. Klimov V.A., Pishchaev D.V., Petrochenkov A.B., Bochkarev S.V., Topical issues related to efficient operation of oil production facilities (In Rus.), Neftyanoe khozyaystvo = Oil Industry, 2020, No. 7, pp. 46–49, DOI: https://doi.org/10.24887/0028-2448-2020-7-46-49

6. GOST 13877-96. Sucker rods and sucker rod couplings. Specifications