This topic will you describe how to prevent well ballooning. There are several items that you can manage in order to prevent or minimize well ballooning.
Trying not to lose fluid or to minimize drilling mud loss into formation is the best way to prevent well ballooning. As you may know from the previous topic, well ballooning basic, before ballooning will happen, you must have downhole losses. Then, flow back will occur when pumps are off.
There are several ways that can help you on this issue as listed below:
It is not simple to identify well ballooning because the well acts almost like well control situation (taking kick). Therefore, this topic describe how to identify well ballooning and important rules when you face with well ballooning situation.
These following guidelines will help you identify ballooning.
• Drilling mud losses – you must have mud loss into formation in order to have mud flow back when pumps off.
• Flow back when pump off and flow rate decrease over time – you must line the well up into a trip tank and monitor well. Tracking volume flow back every minutes help you understand if flow back trend decreases. The key thing is “flow back rate must reduce over time”. If not, you will have well control situation instead. Monitoring well takes time and personnel must be patient.
This topic describes about well ballooning. You may hear several terms besides well ballooning as wellbore breathing or micro fracturing phenomenon.
What is well ballooning?
The well ballooning effect is a natural phenomenon occurring when formations take drilling mud when the pumps are on and the formations give the mud back when the pumps are off.
What is mechanism of well ballooning?
While pumps are on, if Equivalent Circulating Density (ECD) exceeds formation fracture, micro fractures are created and drilling mud will lose into small induced formation fractures. The micro fractures can be propagated and it may cause a lot of mud volume losses down hole. Micro fracture will not cause severe losses or totally losses.