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Definition(s)

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Conductance

Permeability per unit thickness of a static (not in motion) shale-shaker screen. NOTE It is expressed in units of kilodarcies/millimetre. The darcy is not an SI unit. The SI unit of permeability to fluid flow is defined as the amount of permeability that permits 1 m³ of fluid of a viscosity of 1 pascal per second to flow through a section 1 m thick with a cross section of 1 m² in 1 second at a pressure difference of 1 pascal. That unit has no special name. The SI unit of permeability = 1,013 25 × 1012 darcy. Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards  

Definition(s)

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Colloidal Solid

Particle of diameter less than 2 μm. NOTE This term is commonly used as a synonym for clay particle size. Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards  

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Coating

Material applied to the pipe to help prevent corrosion or erosion. Source: IADC UBO / MPD Glossary, December 2011. Global Standards

Coating

Metallic, inorganic or organic material applied to steel surfaces for prevention of corrosion. Source: Offshore Standard DNV-OS-C101, Design of Offshore Steel Structures, General (LRFD Method, Det Norske Veritas, April 2011. Global Standards  

Coating

Permanent deposition of a material onto the surface of a part to enhance its surface properties such as improving corrosion protection, wear resistance, or reducing friction.

Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global Standards

Coating (Substance)

Material adhering to a surface to change the properties of the surface. cf. blinding (3.1.11) Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards  

Coating (Physical Process)

Procedure by which material forms a film that covers the apertures of the screening surface. cf. blinding (3.1.11). Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards

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Clay Particle

Colloidal particles of clay mineral having less than 2 μm equivalent spherical diameter cf. colloidal solid (3.1.20). Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards  

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Clay Mineral

Soft variously coloured earth, commonly hydrous silicate of alumina. NOTE Clay minerals are essentially insoluble in water but disperse under hydration, grinding, heating or velocity effects. Particle sizes of clay mineral can vary from sub-micrometre to larger than 100 μm. Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards  

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Check Section (or Suction Section)

Last active section in the surface system which provides a location for rig pump and mud hopper suction, and ideally is large enough to check and adjust drilling fluid properties before the drilling fluid is pumped downhole. Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards  

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Centrifuge

Device, rotated by an external force, for the purpose of separating materials of various masses (depending upon specific gravity and particle sizes) from a slurry to which the rotation is imparted primarily by the rotating containing walls. NOTE In a weighted drilling fluid, a centrifuge is usually used to eliminate colloidal solids. Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards  

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Centrifugal Pump

Machine for moving fluid by spinning it using a rotating impeller in a casing with a central inlet and a tangential outlet. NOTE The path of the fluid is an increasing spiral from the inlet at the centre to the outlet, tangent to the impeller annulus. In the annular space between the impeller vane tips and the casing wall, the fluid velocity is roughly the same as that of the impeller vane tips. Useful work is produced by the pump when some of the spinning fluid flows out of the casing tangential outlet into the pipe system. Power from the motor is used to accelerate the fluid entering the inlet up to the speed of the fluid in the annulus. Some of the motor power is expended as friction of the fluid in the casing and impeller. Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards  

Centrifugal Pump

Rotating machine device that uses centrifugal force to convert mechanical energy into pressure or head. Source: IADC UBO / MPD Glossary, December 2011. Global Standards  

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Cementing Float Equipment

The term “cementing float equipment” refers to one or more check valves incorporated into a well casing string that prevent fluid flow up the casing while allowing fluid flow down the casing. Source: API RP 10F, Recommended Practice for Performance Testing of Cementing Float Equipment, Upstream Segment, Third Edition, April 2002 (Reaffirmed August 2008). Global Standards  

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Critical Static Gel-Strength Period (CSGSP)

Time interval required for the cement to progress from the critical static gel strength value to a static gel strength of 250 Pa (500 lbf/100 ft2). Source: API RP 10B-6, Recommended Practice on Determining the Static Gel Strength of Cement Formulations, Upstream Segment, First Edition, August 2010. Global Standards