Development status and prospects of rotary sidewall coring technology

Abstract:

Sidewall coring serves as a vital supplement to conventional coring. However， traditional rotary sidewall coring technology is prone to core loss， fragmentation， or coring failure under high-temperature， high-pressure， and high ground stress conditions， making it difficult to meet the demand for high-quality and efficient coring in deep wells and unconventional reservoirs. To address these challenges， this paper systematically reviews the technological progress of typical rotary sidewall coring tools both domestically and internationally， conducting a comparative analysis of their structural parameters and coring principles. It further delves into the influence mechanisms of factors such as formation conditions， coring tool performance， well deviation， filter cake quality， drilling fluid properties， and operational errors on sidewall coring quality. Based on field application data， a comprehensive evaluation is performed on various sidewall coring tools in terms of core recovery rate， integrity， suitability for core analysis， and reliability. The findings indicate that rotary sidewall coring technology holds significant advantages in complex formations and can provide reliable support in terms of petrophysical and geological parameters for the evaluation of deep and ultra-deep reservoirs， while large-size rotary sidewall coring technology markedly enhances sample representativeness. Domestic sidewall coring tools have reached maturity in conventional reservoirs but still have gaps in the lifespan of critical tool components， signal acquisition， and control accuracy. Future technological advancements should focus on key areas such as high-temperature-resistant materials， sealing and anti-contamination design， and multi-parameter adaptive control systems to improve operational precision and environmental adaptability， thereby offering more efficient engineering solutions for core acquisition in complex formations.