This is a tough one. Unlike stick slip, the signs are way more subtle. This post will inform you what we have learned by looking at data. We hope you find it helpful. To identify bit balling from surface data in real-time, we need to be looking for a long-term decrease in torque as well…

So, let us first define “full stick” – at least for use within this post. We define a full stick event as an extreme case of stick-slip, where the bit comes to a complete stop for a slightly “extended” duration. These events are violent and can be extremely damaging to the drill bit, mud motor,…

Stick slip: It is a topic that has been extensively studied and investigated. And there have been many approaches invented to mitigate them over the years. So, you might wonder whether there is anything new to talk about when it comes to stick slip. Perhaps you already know that sometimes a little stick slip is…

We mentioned in last week’s post that we can detect pump failure from EDR data (1Hz to 0.2Hz). We also mentioned that washout and pump failure signatures are so similar that often there is not sufficient basis to differentiate between them. In effect, washout and pump failure signatures are the same except for the flow…

Washouts impact drilling hydraulics and can be a major source of non-productive time especially when it leads to twist-offs and ultimately expensive fishing jobs. It is good therefore to be alerted about a potential washout as early as possible. Here we show how we use a Bayesian network for this purpose. A washout will generally…

By most recent count, Sentinel RT currently houses 20 Bayesian networks within it. Some simple, some complex and some naïve. We will go into each network in detail over the coming weeks and months, but first a non drilling introduction to Bayesian Networks – also sometimes called a Bayesian Belief network – to set the…

Last week, we discussed the human belief system and its use in decision making. It is of course fair to ask if the concept of belief has any mathematical backing. Thankfully, it does. Belief = Probability; the subjective kind, the kind promoted by those who call themselves Bayesians. To understand the mathematics of belief, it…

Sentinel RT is a drilling belief engine. How does that help on a drilling rig? Humans generally make decisions and act on choices based on their beliefs. They tend to form beliefs on a whole variety of topics, over their lifetime, starting right from their childhood. Past events, actions and the outcomes of such actions,…