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A well kill is the operation of placing a column of heavy fluid into a well bore in order to prevent the flow of reservoir fluids without the need for pressure control equipment at the surface. It works on the principle that the hydrostatic head of the "kill fluid" or "kill mud" will be enough to suppress the pressure of the formation fluids. Well kills may be planned in the case of advanced interventions such as workovers, or be contingency operations. The situation calling for a well kill will dictate the method taken. Not all well kills are deliberate. Sometimes, the unintended buildup of fluids, either from injection of chemicals like methanol from surface, or from liquids produced from the reservoir, can be enough to kill the well, particularly gas wells, which are notoriously easy to kill. ==Principles== The principle of a well kill revolves around the weight of a column of fluid and hence the pressure exerted at the bottom. Where P is the pressure at depth h in the column, g is the acceleration of gravity and ρ is the density of the fluid. It is common in the oil industry to use weight density, which is the product of mass density and the acceleration of gravity. This reduces the equation to: Where γ is the weight density. Weight density may also be described as the pressure gradient because it directly determines how much extra pressure will be added by increasing depth of the column of fluid. The objective in a well kill, is to make the pressure at the bottom of the kill fluid equal (or slightly greater) than the pressure of the reservoir fluids. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「well kill」の詳細全文を読む スポンサード リンク
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