Page 45 - igem-g-4 edition 2

IGEM/G/4 Edition 2
strength test pressure (STP)
Pressure to be applied to a system during a strength test.

stress concentration factor (SCF)
Ratio of local stress to a remote reference stress.

stress exception
Term used when the calculated stress on a component/fitting is found to exceed any of the
acceptance criteria for sustained, shakedown or fatigue loading.

stress range
Algebraic difference of stresses at a particular point in the pipe or component, due to
variations in the operating conditions.

strip maps
Maps, to a large scale, showing the route of a pipeline and which may contain marginal notes,
etc., giving information on land usage, ownership etc. and profiles.

structural reliability model
Mathematical or statistical model of a failure mechanism.

structural wall
Timber frame panels with timber studs at nominal centres and a sheathing of plywood or a
similar wood-based board. Insulation (usually mineral wool) is fitted within each panel.

sub-assemblies
Arrangements of pipework and equipment fabricated and assembled independently from the
main pipework configuration often away from site at a manufacturer’s premises.

subsidiary flue
The part of a shared or common flue system that connects the appliance outlet to the main
flue.

sunstock control
Control which automatically removes gas from a low pressure gasholder in which gas has
expanded beyond the high-level limit for any reason.

supplementary firing burner
Burner that is provided with all or most of its combustion air (oxygen) requirements from the
turbine exhaust gases.

survey tools
Downhole equipment and instruments used to determine the position of a bore in directional
drilling or site investigation.

sustained stress
Stress induced in the pipe wall or component which is not changed by distortion or movement.

switchover
Process of changing from firing on one main fuel to firing on another.

system interface
Point of connection between two gas supply systems operated by different companies.

tamper circuit
Circuit built into, or added to, a meter and designed so as to detect and signal any illicit
tampering or interference.

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