Oil and gas glossary

A scale of how light or heavy a crude oil or condensate is. It rises as the liquid gets lighter.

Adding energy so a well can produce after the reservoir can no longer lift the fluids on its own at the wanted rate.

A sucker-rod pump: a surface unit lifts and drops a rod string that drives a plunger pump at the bottom of the tubing.

Pressure in the well at a stated depth, almost always opposite the reservoir or at a downhole gauge.

A restriction, usually at the wellhead, that sets the flowing wellhead pressure and therefore the rate.

A forecast of future rate from the way past rate has fallen with time or with cumulative production.

A multistage centrifugal pump run on the tubing and driven by a downhole electric motor.

The pressure at reservoir depth while the well is producing.

Artificial lift that injects gas into the tubing to lighten the column so the reservoir can flow.

Produced gas rate divided by produced oil rate, both at surface conditions.

The relationship between bottomhole flowing pressure and the rate a well can deliver.

Injection rate divided by how far the injection bottomhole pressure sits above reservoir pressure.

Finding a well's rate by matching what the reservoir can deliver to what the tubing and surface system can carry.

The liquid rate a well delivers for each unit of pressure drawdown.

The removable pipe inside the production casing that carries produced or injected fluids.

The pressure at the top of the tubing, at the wellhead.

How strongly a fluid resists flow.

The fraction of the produced liquid that is water.