دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: the space between two concentric circles. In the petroleum industry, it is usually the space surrounding a pipe in the wellbore, or the space between tubing and casing, or the space between tubing and the well bore;sometimes termed the annulus.

n: The space between a pipe and a hole. The space between drillstring and hole or casing is an Annulus.

n: the rate at which mud is travelling in the annular space of a drilling well.

n: The linear velocity of a fluid passing through an annular space. The term critical annular velocity is often used to describe the flow rate or velocity at which entrained solids will be efficiently transported by the annular fluid. If the fluid velocity f

the velocity of fluids flowing in the annulus. Important in clean-up and displacement processes.

n: see annular space.

n: The space between a pipe and a hole. The space between drillstring and hole or casing is an Annulus.

The area between the O.D. of an inside string and the ID of an outside string.

the mechanism that provides pressure isolation between each casing hanger and the wellhead housing.

n: 1. one of two electrodes in an electrolytic cell;represented as the negative terminal of the cell, it is the area from which electrons flow. In a primary cell, it is the electrode that is wasted or eaten away. 2. in cathodic protection systems, an electrode to which a positive potential of electricity is applied, or a sacrificial anode, which protects a structure by forming one electrode of an electric cell.

the positively charged site in a cell. Oxidation site. The site of metal loss in corrosion.

the ratio of the mass loss of actual corrosion of an anode to the theoretical corrosion mass loss calculated from the quantity of electricity that has passed between the anode and the cathode using Faraday’s law (from NACE).

a formed metal bar (zinc, aluminum, etc.) attached by electrical wire to a structure to be protected and buried in conductive soil near that structure.

polarization to a higher oxidizing potential to achieve a reduced corrosion rate (promotes passivity).