Perforating Flashcards
The calculated flow area provided by perforations across a specific zone of interest
area open to flow
A technique in which several perforating guns are run on a single trip into the well, and then all are fired simultaneously
bank firing
A perforating charge designed to create perforations with a large-diameter entrance hole
big hole charge
A section of heavy walled tubing that is placed across any perforated interval through which the production tubing must pass, such as may be required in multiple zone completions
blast joint
A small metal tube containing secondary high explosive that is crimped onto the end of the detonating cord
booster
A downhole tool that is located and set to isolate the lower part of the wellbore
bridge plug
An early perforating method that used a hardened steel bullet or projectile, propelled by an explosive charge, to create a perforation tunnel
bullet perforating
An exposed gun system used primarily in wireline operations
capsule gun / strip gun
A perforating gun, consisting of a loading tube and shaped charges
carrier gun
A downhole tool used to confirm or correlate treatment depth using known reference points on the casing string
casing collar locator (CCL)
A log provided by a casing collar locator tool that generally incorporates a gamma ray log to correlate the relative position of casing string features, such as the location of a pup joint, with the reservoir or formation of interest
casing collar log
A perforating gun assembly designed to be used in a wellbore before the production tubulars or completion equipment have been installed, thus allowing access for a larger diameter gun assembly
casing gun
A downhole tool run on wireline to sever tubing at a predetermined point when the tubing string becomes stuck
chemical cutter
The rubblized or damaged zone surrounding a perforation tunnel where the action of the perforating charge or bullet has altered the formation structure and permeability
crushed zone
The area surrounding the wellbore that has been harmed by the drilling process, generally as a result of mud or cement-filtrate invasion
damaged zone
A perforating charge designed to provide a long perforation tunnel, such as may be required to bypass any near-wellbore damage
deep penetrating charge
To set off an explosive material
detonate
A cord containing high-explosive material sheathed in a flexible outer case, which is used to connect the detonator to the main high explosive
detonating cord / primer cord
A device containing primary high-explosive material that is used to initiate an explosive sequence
detonator / blasting cap
A safety device used when running and retrieving tools or drill collars with a flush external surface that may easily pass through the rotary table slips
dog collar
A ball that is dropped or pumped through the wellbore tubulars to activate a downhole tool or device
drop ball
A heavy steel bar that is dropped through the tubing or running string to fire the percussion detonator on a tubing-conveyed perforating (TCP) gun assembly
drop bar
A device, shaped like a short length of pipe, which is used to drop TCP guns in the rathole or sump
drop sub
A perforating gun assembly designed to be detached from the tubing or running string after firing
dropoff gun
A value that reflects the number of perforations per unit of length (usually feet) that are producing, or injecting, efficiently
effective shot density
The hole created in the internal surface of the casing or liner by the perforating charge or bullet
entrance hole
A perforating gun assembly that disintegrates upon firing, thereby reducing the volume and dimensions of retrieved components
expendable gun
A pipe-shaped housing that protects the firing head of a tubing-conveyed perforating gun
fill sub
A mechanical or electronic device used to detonate perforating charges conveyed by tubing, drillpipe, coiled tubing or slickline
firing head
A specialized perforating-gun system that contains shaped charges loaded at 0°, 60°, 120°, or 180° phase angles to provide a casing entrance hole of approximately 0,5 in [1,3 cm], which is intended to be large enough for hydraulic fracturing operations
frac gun
A perforating-gun system containing big-hole or gravel-pack charges
gravel pack gun
A device used to perforate oil and gas wells in preparation for production
gun
The point on a gun assembly or perforating string that is used when correlating depth
gun zero
Chemical explosive material having an extremely high reaction rate that creates very high combustion pressures, unlike low explosives that have a much lower reaction rate and are commonly used as propellants
high explosive
A perforating gun having more than four shots per foot
high shot density gun
A perforating gun, consisting of a loading tube and shaped charges
hollow carrier gun
The use of shaped explosive charges to create perforation tunnels
jet perforating
A surface detection system used to ensure that all tubing-conveyed perforating guns have fired, from the top shot to the bottom shot
last-shot detection
The reduction in permeability in the near-wellbore area resulting from mechanical factors such as the displacement of debris that plugs the perforations or formation matrix
mechanical skin
A column of high-pressure nitrogen typically applied to a tubing string in preparation for drillstem testing or perforating operations in which the reservoir formation is to be opened to the tubing string
nitrogen cushion
To create holes in the casing or liner to achieve efficient communication between the reservoir and the wellbore
perforate
To create holes in the liner or casing under conditions in which the hydrostatic pressure inside the casing or liner is greater than the reservoir pressure
perforate overbalanced
To create holes in the liner or casing under conditions in which the hydrostatic pressure inside the casing or liner is less than the reservoir pressure
perforate underbalanced
The section of wellbore that has been prepared for production by creating channels between the reservoir formation and the wellbore
perforated interval
A wellbore tubular in which slots or holes have been made before the string is assembled and run into the wellbore
perforated liner
An acid treatment placed in the wellbore over the interval to be perforated
perforating acid
An explosive device that utilizes a cavity-effect explosive reaction to generate a high-pressure, high-velocity jet that creates a perforation tunnel
perforating charge / shaped charge
perforating charge / shaped charge
A wireline log run to provide a means of depth correlation by comparing the position of casing collars to the reference log (gamma ray log)
perforating depth control log
A specially prepared fluid placed in the wellbore over the interval to be perforated
perforating fluid
A device used to perforate oil and gas wells in preparation for production
perforating gun
The number of perforations per linear foot
perforation density
A measure, or indicator, of the length that a useable perforation tunnel extends beyond the casing or liner into the reservoir formation
perforation penetration
The radial distribution of successive perforating charges around the gun axis
perforation phasing
Electric detonators used in wireline and electronic firing-head perforating operations, which are immune to radio interference and thus cannot be accidentally triggered by radio transmissions
radio safe detonator
A procedure imposed during perforating operations in which radios at or near the wellsite are switched off to prevent accidental detonation of perforating guns
radio silence
A perforating gun designed to be retrieved from the wellbore after firing
retrievable gun
A blank gun section or spacer installed between the top perforating-gun assembly and firing head in a TCP operation
safety spacer
A perforating gun with a recess profile in the perforating gun body adjacent to the shaped charge
scallop gun
The technique of selectively firing successive perforating guns arranged in a multiple gun assembly
selective firing
A technique used to fire individual perforating guns when multiple guns have been run together in a single trip into the well
selective perforating
A short piece of brass or steel that is used to retain sliding components in a fixed position until sufficient force is applied to break the pin
shear pin
To perforate a wellbore in preparation for production
shoot a well
A surface detection technique to verify that perforating guns have fired
shot detection
The geometric profile around a correctly placed perforation
stable arch
The space between the shaped charge and the internal surface of the perforating gun body
standoff
The use of tubing,drillpipeor coiled tubing to convey perforating guns to the required depth
TCP / tubing conveyed perforating
A perforating gun assembly designed to run through the restricted clearance of production tubing, then operate effectively within the larger diameter of thecasingorlinerbelow
through tubing gun
A special perforating gun, or charge, that is designed for limited penetration to allow an inner tubing or casing string to be perforated without damaging a surrounding outer string
tubing puncher
