IWCF WIPC Level 2 flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Hydrostatic pressure formula

Hydrostatic pressure in psi equals 0.052 multiplied by fluid density in ppg multiplied by true vertical depth in feet. Use TVD, not measured depth, for all pressure calculations.

Kill-weight mud formula

Kill weight in ppg equals current mud weight plus shut-in drill pipe pressure in psi divided by 0.052 times TVD in feet. This assumes the drill pipe is not plugged and pressure is stable.

Two-barrier policy

At least two independent, tested barriers must separate the reservoir from the atmosphere at all times. A single barrier is allowed only for short, risk-assessed operations with management approval.

Bullheading

Pumping fluid into the well to displace formation fluid back into the reservoir. Used when circulation is not possible or when the string is plugged; requires pressure ratings above maximum anticipated surface pressure.

Lubricate and bleed

A well-control method where kill fluid is pumped into the well and gas is bled from the top, gradually replacing formation fluid with kill fluid while keeping bottomhole pressure above formation pressure.

Tubing hanger function

The tubing hanger lands and seals the completion string in the wellhead. It supports string weight and provides a secondary barrier for annulus pressure. It must be tested after installation.

Production packer

A downhole tool that isolates the tubing-casing annulus. It is set mechanically, hydraulically, or by wireline. It must be pressure-tested before the well is displaced or put on production.

Subsurface safety valve

A fail-safe closed valve, usually a flapper, installed in the tubing. It is held open by hydraulic control line pressure and must be tested at prescribed intervals to verify closure.

Gas lift valve

A valve that admits lift gas into the tubing to lighten the fluid column. It contains a check valve to prevent reverse flow. Spacing depends on unloading gradient and injection pressure.

Tubing movement

Thermal expansion, ballooning, and piston effects change tubing length during production. The packer and seal assembly must accommodate movement without unseating or overstressing the tubing.

Elastomer compatibility

Seals must be rated for the temperature, pressure, and produced fluids. CO2 and H2S can cause swelling or degradation. Confirm material compatibility before running the completion.

Landing nipple

A completion accessory with an internal profile that accepts a lock mandrel for plugs or valves. No-go nipples limit the size of tools that can pass through.

Coiled tubing fatigue

Each trip over the gooseneck and reel induces bending cycles that consume fatigue life. Remaining life is tracked in cycles and is a hard limit; exceeding it can cause string failure.

Stripper element

A sealing element in the coiled tubing BOP stack that seals around the moving pipe. A worn or leaking stripper is a well-control hazard and must be replaced.

CT force model

A calculation of pick-up and slack-off loads along the coiled tubing string, accounting for friction, buoyancy, and buckling. It sets safe operating limits below string yield and connector rating.

CT depth correlation

Coiled tubing depth is measured at surface. Stretch, thermal expansion, and helical buckling cause depth error; correct before correlating with wireline or casing depths.

Slickline

A single solid wire used for mechanical work such as shifting sleeves, setting plugs, or fishing. It carries no electrical power and relies on toolstring weight and mechanical jars.

Braided wireline

A multi-strand wire containing electrical conductors. It powers downhole tools such as perforating guns, logging tools, and powered mechanical devices.

Grease injection

Pumping grease into the stuffing box at pressure above well pressure to seal around the wire. Loss of grease return or pressure indicates a seal problem and potential well-control issue.

Weak point

A component in the wireline toolstring designed to part at a load below the wire strength. It allows recovery of the wire if the toolstring becomes stuck.

Wireline depth stretch

Wire stretches under its own weight and toolstring load, causing depth error. Depth must be corrected using tension and wire properties before placing plugs or perforators.

Radio silence

A mandatory period when explosive actuators are armed at the wellsite. All radios and electrical devices are shut down to prevent accidental detonation.

Snub force calculation

Snub force in pounds equals well pressure in psi times pipe cross-sectional area in square inches, minus pipe weight in air. A positive result means snubbing is required; negative means pipe-heavy.

Stripping preventer

A BOP component that seals around pipe being moved through it under pressure. It wears with use and must be monitored and replaced when sealing performance degrades.

Critical buckling load

The compressive load at which pipe buckles. Snubbing pipe in compression must stay below this load; centralizers and proper pipe selection reduce buckling risk.

Blind rams

BOP rams that close and seal the wellbore when no pipe is present. In an emergency, blind rams are closed to isolate the well.

Shear rams

BOP rams designed to cut pipe in the hole and seal the wellbore. They must be capable of cutting the specific pipe size and grade in use.

Hydrate formation

Ice-like solids formed when gas and water combine at low temperature and high pressure. Prevent with methanol or glycol injection and by controlling pressure and temperature.

Riser margin

The additional mud weight needed to compensate for loss of the riser's hydrostatic pressure if the riser is disconnected. Loss of riser integrity can cause a kick.

Emergency disconnect

The lower marine riser package can disconnect from the subsea BOP stack in an emergency. The sequence must be known, practiced, and tested.

Subsea tree valves

Valves on the subsea tree are fail-safe closed and hydraulically actuated. Their function and response time must be verified before operations.

Subsea pressure rating

All subsea equipment must be rated for the water depth and maximum anticipated pressure at the mudline. Exceeding the rating risks equipment failure and loss of well control.