دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

v: to join metals by utilising the arc created between the welding rod, which serves as an electrode, and a metal object. The arc is a discharge of electric current across an air gap. The high temperature generated by the arc melts both the electrode and the metal, which fuse.

a phenomenon in which fluids are lost to the rock during over-pressured operations, such as found in increased pressures from equivalent circulating density operations, and then flow back when pressure is reduced. This may be confused with a kick.

n: on a diamond bit, the material (usually powdered and fused tungsten carbide) into which the diamonds are set.

the specific gravity of the set well cement, generally about 3.15 for Portland cement. Do not confuse with slurry density.

n: a compressor in which the flow of gas to be compressed is moved away from the centre rapidly, usually by a series of blades or turbines. It is a continuous-flow compressor with a low pressure ratio and is used to transmit gas through a pipeline. Gas passing through the compressor contacts a rotating impeller, from which it is discharged into a diffuser, where its velocity is slowed and its kinetic energy changed to static pressure. Centrifugal compressors are nonpositive-displacement machines, often arranged in series on a line to achieve multistage compression.

n: In drill fluid, in order to keep electric neutrality the clay colloids which carry negative charge must attract the same number of cations.As a result,an electric layer forms in the interface between Solid and liquid. Some cations

n: a device that uses part of the kinetic energy of a fluid passing through a machine by gradually increasing the cross section of the channel or chamber through which it flows so as to decrease its speed and increase its pressure.

n: A kind of center blower whose entry diameter is smaller than its exit diameter so that the velocity energy can be changed into force energy .