In oil or gas well drilling, lost circulation[1][2][3] occurs when drilling fluid, known commonly as "mud", flows into one or more geological formations instead of returning up the annulus. Lost circulation can be a serious problem during the drilling of an oil well or gas well.

2015年6月30日 · Loss of circulation is the uncontrolled flow of whole mud into a formation, sometimes referred to as a “thief zone.” This article discusses causes, prevention, and remedial measures for lost circulation. Fig. 1 shows partial and total lost-circulation zones.

2023年9月29日 · Lost circulation is considered as one of the difficult troubles which handling during drilling operations. It may create a variety of concerns, including increased non-productive time and drilling costs. The degree of the results varies based on the extent of the loss. It might begin with just losing fluids and progress to blowout.

6 天之前 · Fig. 1 shows partial and total lost-circulation zones. In partial lost circulation, mud continues to flow to surface with some loss to the formation. Total lost circulation, however, occurs when all the mud flows into a formation with no return to surface. If drilling continues during total lost circulation, it is referred to as blind drilling.

2014年12月8日 · Lost circulation is a situation when drilling fluid losses downhole because formation (s) is fractured. There are three levels of lost circulation which are seepage loss, partial loss and total loss. Seepage loss is a situation when the mud volume loses into formation at very minimal and this will have no or little effect for a drilling operation.

Lost Circulation is defined as the loss of whole mud (solids and liquid) into the formation. A severe lost-circulation event can cost a million dollars or more from delays and fluid losses and sometimes result in losing the well.

2021年1月18日 · In this article, we will handle their effects, types, types of thief zones, first actions & methods for locating loss zones. Also, we will cover the causes, remedial, LCM & preventive actions for lost circulation problems in other articles.