This study proposes a methodology to diagnose the root causes of failures in the domain of oil well drilling. The idea is to combine a Bayesian network, which is generated based on an expert knowledge, with situation-specific knowledge of past failure cases. A causal chain is viewed as a temporal sequence. To test the model’s capability, six failure cases from the study’s application domain (oi...

Synthetic-based drilling muds (SBMs) offer excellent technical characteristics while providing improved environmental performance over other drilling muds. The low acute toxicity and high biodegradability of SBMs suggest their discharge at sea would cause minimal impacts on marine ecosystems, however, chronic toxicity testing has demonstrated adverse effects of SBMs on fish health. Sparse envir...

In order to carry out a series of key basic researches, a scientific ultra-deep drilling plan is being undertaken in China. Wellbore temperature is one of the key factors during the drilling process. In this paper, we established a twodimensional transient numerical model to predict the ultra-deep wellbore temperature distributions during circulation and shut-in stages. The simulation results i...

The costs associated with drilling and completing wells are a major factor in determining the economic feasibility of producing energy from geothermal resources. In EGS power plants, estimates place drilling costs as accounting for 42%-95% of total power plant costs (Tester et al., 1994) depending on the quality of the EGS reservoir. An earlier correlation first developed by Milora and Tester (...

To enhance solubility and the performance of a plant gum (from south peach tree of China, SP gum) as a drilling fluid additive, we explored the potential of Modified SP (MSP) gum by modifying it with epichlorohydrin. The modification conditions, such as the mass ratio of  the crosslinking agent, pH and temperature, were optimized and the results show that 56.40 g/100g mass ratio of the cros...

Data is generally expected to continue its exponential growth the next five to ten years. However, it is commonly agreed that the amount of data that currently exist is abundant and that there is still much to achieve with it. The industry, in general, has recognized both the growth and the need to analyze the data. This is also the case with oil well drilling operations. Currently, operators m...

The technical focus of drilling operations is changing to oil and gas reservoirs with higher difficulty factors such as low permeability fracture. During the process, in deep complex formations are prone overflow leakage complications. Leakage problems will change performance fluid wellbore, impacting wellbore pressure, causing accidents stuck collapse. In order improve level control over risk ...