ANSI API RP 17G:2006 pdf download

ANSI API RP 17G:2006 pdf download.RecommendedI Practice for Completion/Workover Risers.
3.1 .1 06
primary load
load which is independent of structural deformation in the riser and induces an internal force that is necessary to satisfy the laws of static equilibrium
NOTE The internal force acts as long as the load is applied, and does not diminish when yielding occurs.
EXAMPLE Internal pressure, external hydrostatic pressure, self-weight, contents and buoyancy of the riser.
3.1 .107
primary stress
stress that satisfies the laws of equilibrium of pressure, external force and moment (i.e. load effects)
NOTE 1 Regarding the mechanical behaviour of a structure, the basic characteristic of this type of stress is that in case of (non-admissible) increment of external load, the deformations upon full plasticification of the section considerably ncreases without being self-limiting.
NOTE 2 Regarding primary stress, distinction is made between membrane stress and bending stress with respect to their distribution across the cross-section governing the load-carrying behaviour. Primary membrane stress is defined as the average value of the respective stress components distributed over the section governing the load-carrying behaviour. Primary bending stress is defined as primary stress distributed linearly across the considered section and proportional to the distance from the neutral axis.
NOTE 3 Regarding the distribution of membrane stress along the wall, distinction is made between general primary membrane stress and local primary membrane stress. Membrane stress due to gross structural discontinuities (e.g. integral attachments) is considered as local.
3.1 .1 08
process shutdown
controlled sequence of events that ensures that the well is secured against accidental release of hydrocarbons to the environment
3.1.1 09
prying
magnification of an external load by a pseudo-lever action when the load is an eccentric tensile load
3.1.110
pup joint
joint of pipe or tubing shorter than standard length
3.1.111
purchaser
organization that buys the CIWO riser system on behalf of the user and/or operator or for its own use
3.1 .112
ratcheting
progressive inelastic deformation or strain which can occur in a component that is subjected to variations of mechanical stress, thermal stress, or both (thermal stress ratcheting is partly or wholly caused by thermal stress)
NOTE Ratcheting results in a plastic deformation, which increases by about the same amount at each cycle and quickly leads to an unacceptable value.
3.1 .113
re-entry spool
uppermost part of a subsea tree to which the C’WO riser is attached to gain vertical well access or the uppermost part of a lower workover riser package to which an emergency disconnect package connector is attached to provide a single disconnect point
3.1.114
resistance
mechanical property of a component, a cross-section, or a member of the structure, e.g. bending resistance, local buckling resistance
3.1 .115
response amplitude operator
RAO
relationship between wave surface elevation amplitude and the vessel response amplitude, and the phase lag between the two
3.1 .116
retainer valve
valve assembly in the C/WO riser used to retain fluid within the riser and hence preventing its escape to the environment during a riser disconnect operation
NOTE Typically located just above the disconnect point.
3.1 .117
return period
average period of time between occurrences of a given event
NOTE The inverse of the return period is the statistical probability of such an event occurring in any given year.
3.1 .118
riser disconnect
operation of unlatching a riser connector
EXAMPLE Disconnecting the emergency disconnect package from the lower riser package and/or disconnecting the riser from the subsea test tree.
3.1 .119
riser joint
joint consisting of a tubular member(s) midsection, with riser connectors at the ends
NOTE Riser joints are typically provided in 9,14 m to 15,24 m (30 ft to 50 ft) lengths. Shorter joints, pup joints, can also be provided to ensure proper space-out while running the subsea tree, tubing hanger, or during workover operations.
3.1 .120
riser model
structural model, established from the tabulated data of the riser, to describe the actual riser, and used in a global analysis of the riser system
3.1.121
riser pipe
seamless pipe which forms the principal conduit of the riser joint
EXAMPLE The riser pipe is the conduit for containing the production fluid flow from the well to the surface tree.
3.1.122
riser system
comprises the riser and all integrated components including subsea and surface equipment
EXAMPLE In tubing hanger mode, the system includes all components from tubing hanger to the top drive; in tree mode, the system includes all components from the wellhead to the top drive.
3.1.123
rotary table
device used to apply torque to the drill string during drilling and normally located in the centre of the drill floor
NOTE Can be rotated and can support wear bushing or spider.