Wall Thickness Module
The FieldTwin Wall Thickness module calculates the wall thickness of a rigid (single wall) pipeline/riser/jumper using basic calculations derived from either the API RP 1111 (4th Edition) or DNVGL OS-F101 (2013 Edition) industry guidelines. The wall thickness values provided by the FieldTwin Wall Thickness Module only consider the burst and collapse design load cases.
The module estimates two wall thickness values...
One that follows a methodology for the burst design load case and another value that uses a methodology for the collapse design load case. The single value returned by the Wall Thickness module will be the larger of these two values. When the user transfers the wall thickness value to the connection’s metadata model, only the wall thickness value from one of the two design codes can be selected
Project Level Input Parameters
The FieldTwin Wall Thickness module has several input parameters that are defined at the project level. These Project Level input parameters, with the default values set by FieldTwin.
Unless there is a compelling reason for changing the default values for the first four (4) parameters [Modulus of Elasticity of the pipeline metal; Poisson’s ratio, Seawater density, or the magnitude of the gravitational acceleration], FutureOn recommends using these default values. The values for Modulus of Elasticity and Poisson’s ratio are typical values for pipeline low-alloy carbon steel.
The Elevation Reference Height is the location in the pipeline system where the Maximum Design Pressure is specified. It is often above mean sea level (MSL) at a specific location on a platform. The wall thickness calculator assigns this elevation reference height to be at MSL (with a value of 0.0 meter). It must be entered in units of meter, with a positive value showing that the Elevation Reference Height is above the MSL.
Connection Input Parameters needed
The FieldTwin Wall Thickness module needs eight input parameters from the selected connection’s metadata model. These eight input parameters are:
- Maximum Design Pressure
- Maximum Design Temperature
- Connection Outer Diameter
- Minimum Internal Pressure
- Pipe Corrosion Allowance
- Pipe Grade (X60, X65, etc.)
- Fabrication Process
- Service (Oil, Gas Injection, Water Injection, etc.)