Tie Downs

Tie Downs

Definition(s)

Tie Downs

Used to secure lines and system components on land and offshore drilling rigs, particularly important in underbalance drilling operations, where vibration is encountered. Specialist tie down equipment is available. Also, anchoring device for the deadline of a hoist block arrangement. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Throughput

Throughput

Definition(s)

Throughput

Actual flow rate of fluid to flow through the system. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Thermal Expansion

Thermal Expansion

Definition(s)

Thermal Expansion

As temperature increases, fluid volume increases thus decreasing the specific gravity. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
System Curve

System Curve

Definition(s)

System Curve

Line graph that shows how variables like viscosity, density, and flow rate combine with fixed conditions such as length of pipe, inside diameter of pipe, internal roughness of pipe, and changes in elevation influence throughput. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Sweep

Sweep

Definition(s)

Sweep

A procedure that accelerates gas velocity, or increases gas turbulence, through a specific section of line or vessel, for removing accumulated liquids. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Sustainable Capacity

Sustainable Capacity

Definition(s)

Sustainable Capacity

Average sustainable flow rate over long periods taking into account routine maintenance and operating problems. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Supervisory Control and Data Acquisition (SCADA)

Supervisory Control and Data Acquisition (SCADA)

Definition(s)

Supervisory Control and Data Acquisition

A generic name for a computerized system that is capable of gathering and processing data and applying operational controls to geographically dispersed assets over long distances. Adapted from: NCSD Glossary, CNSSI 4009. Source: NICCS™ Portal Cybersecurity Lexicon, National Initiative for Cybersecurity Careers and Studies (https://niccs.us-cert.gov/glossary) as of 11 November 2015, Global Standards

Supervisory Control and Data Acquisition (SCADA)

Computer and communications system that gathers and analyzes operating data and sends reports to the control center. In addition, the SCADA system carries out commands issued by the operator at the control center. Source: IADC UBO / MPD Glossary, December 2011. Global Standards  

Supervisory Control and Data Acquisition

A computer-based monitoring and control system that collects, displays, and stores information from remotely located data collection units and sensors to support the control of equipment, devices, and facilities.

Source: Canadian Standards Association, Z246.1-09, Security management for petroleum and natural gas industry systems, August 2009, Regional Standa

Suction Valve

Suction Valve

Definition(s)

Suction Valve

ON/OFF valve, such as a gate valve or a ball valve. If the valve is open, fluid can flow into the pump or compressor. If the valve is closed, no fluid can flow into the pump or compressor. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Storm Choke

Storm Choke

Definition(s)

Storm Choke

A choke that is pre–set to close automatically if flow exceeds its pre–set rating. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Stripping Out

Stripping Out

Definition(s)

Stripping Out

The process of raising the drill string out of the wellbore when the well is live. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Stripping In

Stripping In

Definition(s)

Stripping In

The process of lowering the drill stem into a well when the well is live. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Stripper Rubbers

Stripper Rubbers

Definition(s)

Stripper Rubbers

Internal component of rotating head used to strip pipe in and out of hole, available for drill pipe and casing sizes, and may be polyurethane composition where required to suit application / conditions e.g., high temperature service, or in certain drilling fluid applications where standard elastomers are inappropriate. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Stripper Head

Stripper Head

Definition(s)

Stripper Head

Blowout prevention device consisting of a gland and packing arrangement bolted to a wellhead. Used to seal annular space between tubing and casing. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Studded Block

Studded Block

Definition(s)

Studded Block

A solid block of metal bored and studded to accept flanges. Used for erosion points or high stress connections. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Steep Characteristic Curve

Steep Characteristic Curve

Definition(s)

Steep Characteristic Curve

Rising pump H-Q curve, with a large increase in head between the head developed at design capacity and at shut-off storage field. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Steady State Model

Steady State Model

Definition(s)

Steady State Model

Performs offline simulation that does not allow for changing line or vessel conditions over time. Stead-state models are the historical norm for facilities planning and quick evaluation of operational situations. It remains an essential step in the transient modeling process. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Steady State Energy Equation

Steady State Energy Equation

Definition(s)

Steady State Energy Equation

Modification of Bernoulli's equation that accounts for friction and work added by pumps. It compares the energy in a fluid at two different points and accounts for the addition or removal of energy between the same two points. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Steady State Analysis

Steady State Analysis

Definition(s)

Steady State Analysis

Method of flow analysis of a line or vessel system that assumes constant flowing conditions. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Steady State

Steady State

Definition(s)

Steady State

For steady state to occur the flow into a pipe must equal the flow through the pipe that must equal the flow out of the pipe. Steady state also has no change in flow or pressure with respect to time. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Station Suction Valve

Station Suction Valve

Definition(s)

Station Suction Valve

ON/OFF valve that allows fluid to enter a station when open, and forces fluid to bypass a station when closed. Operates together with the bypass valve. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Station Differential

Station Differential

Definition(s)

Station Differential

Pressure difference between the station suction pressure and the station discharge pressure. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Station Bypass

Station Bypass

Definition(s)

Station Bypass

Diverting a full or reduced flow in the line or vessel around a shut down station. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Static Resistance

Static Resistance

Definition(s)

Static Resistance

Sum of the elevation head and static head that must overcome before any liquid begins to flow. Source: IADC UBO / MPD Glossary, December 2011. Global Standards