4.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1.1
amplitude
vertical height of the A-scan received signal, measured from base to peak or peak to peak
4.1.2
A-scan display
ultrasonic instrument display in which the received signal is displayed as a vertical height or "pip” from the horizontal-sweep time trace, while the horizontal distance between two signals represents the material distance for time of travel between the two conditions causing the signals
4.1.3
back reflection
signal received from the back surface of a surface test object
4.1.4
bevel diameter
outer diameter of the contact face of the rotary shouldered connection
4.1.5
bit sub
sub, usually with two box connections, that is used to connect the bit to the drill stem
4.1.6
box connection
threaded connection on oilfield tubular goods (OCTG) that has internal (female) threads
4.1.7
bending strength ratio
BSR
Ratio of the section modulus of a rotary shouldered box at the point in the box where the pin ends when made up, to the section modulus of the rotary shouldered pin at the last engaged thread
4.1.8
calibration system
documented system of gauge calibration and control
4.1.9
cold working
plastic deformation of the thread roots of a rotary shouldered connection, of radii and of cylindrical sections at a temperature low enough to ensure or cause permanent strain of the metal
4.1.10
decarburization
loss of carbon from the surface of a ferrous alloy as a result of heating in a medium that reacts with the carbon at the surface
4.1.11
depth prove-up
act of grinding a narrow notch across a surface-breaking indication until the bottom of the indication is located and then measuring the depth of the indication with a depth gauge for comparison to acceptance criteria
4.1.12
drift
gauge used to check minimum internal diameter of drill stem components
4.1.13
drill collar
thick-walled pipe used to provide stiffness and concentration of mass at or near the bit
4.1.14
drill pipe
length of tube, usually steel, to which special threaded connections called tool joints are attached
4.1.15
forge, verb
(hammer) plastically deform metal, usually hot, into desired shapes by the use of compressive force, with or without dies
4.1.16
forging, noun
(product) shaped metal part formed by the forging method
4.1.17
full-depth thread
thread in which the thread root lies on the minor cone of an external thread or on the major cone of an internal thread
4.1.18
gauge point
plane perpendicular to the thread axis in API rotary shouldered connections
NOTE The gauge point is located 15,9 mm (0.625 in) from the shoulder of the product pin.
4.1.19
gas-tight
capable of holding gas without leaking under the specified pressure for the specified length of time
4.1.20
heat, noun
metal produced by a single cycle of a batch melting process
4.1.21
H2S trim
all components, except external valve body, meeting the H2S service requirements of ISO 15156-2 and ISO 15156-3
NOTE For the purposes of this provision, NACE MR0175 is equivalent to ISO 15156-2 and ISO 15156-3.
4.1.22
kelly
square or hexagonally shaped steel pipe connecting the swivel to the drill pipe that moves through the rotary table and transmits torque to the drill stem
4.1.23
kelly saver sub
short rotary sub that is made up onto the bottom of the kelly to protect the pin end of the kelly from wear during make-up and break-out operations
4.1.24
label
dimensionless designation for the size and style of a rotary shouldered connection
4.1.25
length of box thread
LBT
length of threads in the box measured from the make-up shoulder to the intersection of the non-pressure flank and crest of the last thread with full thread depth
(to be continued)
Abstract from Specification for Rotary Drill Stem Elements API 7-1 / ISO 10424
