High Signal Converter

High Signal Converter

Definition(s)

High Signal Converter

Relay that compares two error signals, selects the highest one, and sends this to the final control element. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Head-Capacity Curve

Head-Capacity Curve

Definition(s)

Head-Capacity Curve

Graphical representation of the relationship between the head and the flow rate for a centrifugal pump or compressor.. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Hard Shut In

Hard Shut In

Definition(s)

Hard Shut In

To close in a well with the bop having the choke or choke line valve closed. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
High Recovery Pressure Control Valve

High Recovery Pressure Control Valve

Definition(s)

High Recovery Pressure Control Valve

Valve that recovers a significant percentage of the pressure differential from inlet to the vena contracta. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Heater

Heater

Definition(s)

Heater

Device that increases the temperature of the fluid flowing through the heater. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Heat Exchanger

Heat Exchanger

Definition(s)

Heat Exchanger

Vessel that permits heat exchange between hot and cold fluids. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Header

Header

Definition(s)

Header

  1. collection of valves or short pipes connecting all the flow line in a given area.
  2. modeling term for a short pipe which is treated as a steady state device in transient programs.
Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Graph

Graph

Definition(s)

Graph

Visual method of showing the relationship between two or more characteristics. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Glycol

Glycol

Definition(s)

Glycol

Dihydric alcohol where different carbon atoms bond to the two-hydroxyl groups. The general formula for a glycol is (CH2)n(OH)2. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Globe Valve

Globe Valve

Definition(s)

Globe Valve

Valve that opens or closes when a plug attached to the stem moves linearly in the spherical valve body. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Gauge Pressure

Gauge Pressure

Definition(s)

Gauge Pressure

Measured relative to the ambient pressure (e.g. atmospheric for surface application, hydrostatic for subsea application), measured in “psig”. Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global Standards

Gauge Pressure

Pressure relative to atmospheric pressure. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Gas-Lift Mandrel

Gas-Lift Mandrel

Definition(s)

Gas-Lift Mandrel

A gas-lift system assembled with the production tubing string to provide a means of deploying gas-lift valves. The position or depth of the gas lift valves is crucial to the efficient operation of the entire system. Consequently, proper assembly of the gas lift mandrels within the completion tubulars is essential. A port in the gas-lift mandrel provides communication between the lift-gas supply in the tubing annulus and the production- tubing conduit. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Gas Horsepower

Gas Horsepower

Definition(s)

Gas Horsepower

Total horsepower available to a compressor before derating for mechanical and thermal inefficiencies. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Gage Joint

Gage Joint

Definition(s)

Gage Joint

The heaviest wall casing in the well usually located just beneath the preventers or tree.. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Frictional Pressure Loss

Frictional Pressure Loss

Definition(s)

Frictional Pressure Loss

Difference between the upstream discharge pressure and downstream suction pressure due to friction; the amount of energy lost between nodes depends on flow rate, pipe size, and fluid characteristics. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Friction Head Loss

Friction Head Loss

Definition(s)

Friction Head Loss

Resulting loss of head pressure due to friction in a fluid flowing in a pipe; the head is converted to thermal energy. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Friction Factor

Friction Factor

Definition(s)

Friction Factor

Determined experimentally or empirically by correlating the Reynolds number and the pipe relative roughness to the fluid friction in a flowing pipe; used by some flow equations to calculate pipe pressure loss. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Friction

Friction

Definition(s)

Friction

Resistive force of particles sliding over one another damping out motion. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Fracturing

Fracturing

Definition(s)

Fracturing

A method of breaking down a formation by pumping fluid at very high pressures. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Fluid Flow

Fluid Flow

Definition(s)

Fluid Flow

State in fluid dynamics of fluid in motion determined by fluid type, properties, geometry and velocity. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Flow Switches – Liquid Volumetric

Flow Switches – Liquid Volumetric

Definition(s)

Flow Switches - Liquid Volumetric

A device with a switch output based on the measured flow of a moving liquid in terms of volume per unit time (for example, gallons per hour). Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Flow Switches – Gas Volumetric

Flow Switches – Gas Volumetric

Definition(s)

Flow Switches - Gas Volumetric

A device with a switch output based on the measured flow of a moving gas in terms of volume per unit time (for example, cubic feet per minute). Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Flow Switches Gas & Liquid Velocity

Flow Switches Gas & Liquid Velocity

Definition(s)

Flow Switches Gas & Liquid Velocity

A device with a switch output based on the measured flow of a moving fluid or gas in terms of velocity (e.g. feet per second). Source: IADC UBO / MPD Glossary, December 2011. Global Standards