Drilling Hazards Inventory: The Key to Safer -and Cheaper-Wells

Abstract

Abstract Safety and cost control are critical success factors in the realm of drilling. Actual well costs frequently exceed planned costs due to unexpected drilling incidents related to potentially avoidable geohazards. It is estimated that - in the Netherlands on average - around 20% of drilling time is spent recovering from such unexpected incidents. A significant part of this non-productive time (NPT) can be avoided if geohazards are identified upfront. The risk assessment for a well trajectory is largely based on the experience from offset wells: boreholes in the neighbourhood that have been drilled earlier or holes drilled through similar geological settings. Easy access to relevant historic drilling data and the records of geohazards encountered in offset wells is essential for effective de-risking of future drilling programs. Currently operators typically have their own databases containing this type of information. However, their databases are often incomplete and lack data from competitor wells. Obviously, the risk assessment would greatly benefit from access to a complete set of drilling hazard data, whilst making use of "best practices" in data analyses and incident classification. EBN B.V., the Dutch state E&P company with 0.5 million BOE/d equity production, is involved in most of the 40+ wells being drilled annually in the Netherlands. Recognising its major vested interest in improved drilling performance, EBN launched a Joint Industry Project to capture the knowledge of drilling hazards across the Industry. An important tool to classify drilling incidents is the Drilling Incidence Triangle. Based on this new concept, those drilling incidents that have a geological component are selected, analysed and made accessible for the Industry partners.