Line types: Data

The line types form defines the properties of a number of named line types, which may be referenced by line sections to define their structure and physical properties.

This form must include all the line types referred to by the lines in the model; it can also include other line types that are not currently by any lines. This allows you to collect their data in a library of standard line types, for their easy use when building lines in OrcaFlex.

There is not enough room on the screen to show all the data for more than one line type, so OrcaFlex offers different view modes:

• Individual mode displays one selected line type at a time, but shows you all its data.
• All mode lists the data for all the line types but the data are grouped onto different pages, only one of which is visible at a time.
• External function parameters mode displays the data used by any external functions referenced by the selected line type.

The line type wizard is available to help set up line type data to represent commonly used structures such as chains, ropes etc.

Line type name

Each line type has a unique name.

Category

All line types fall into one of the following categories.

Homogeneous pipe

Appropriate for a pipe constructed from a single homogeneous material, for example a metal riser, or when modelling stress joints and bend stiffeners. The pipe's structural properties are defined by Young's modulus, material density and inner and outer diameters. Both inner and outer diameters may be defined as varying with arc length, allowing the modelling of stress joints and bend stiffeners, for instance.

Equivalent line

Intended for simple modelling of pipe-in-pipe and pipe-on-pipe lines. OrcaFlex calculates the overall line type properties (geometry, mass, stiffness etc.) resulting from the combination of a number of different line types. Note that the data for equivalent line types can only be modified when using the individual view mode.

General

The general category is used in all other situations. The axial, bending and torsional stiffnesses are entered directly, instead of being calculated from $E$. Similarly, mass is given per unit length, rather than calculated from a material density. This direct approach gives complete control over the data, allowing the analysis of flexible risers, umbilicals, hoses, mooring chains, ropes, wires, bundles, seismic arrays, power cables, nets etc.