The project sidebar for this example is shown in the figure below. The project sidebar shows all of the components that are used in the example. Each of these components is described in detail in the following sections.
Project Sidebar for Example 9
When a new PipeLay project is created it contains just a Project component. This component is used to store general project information such as the project title, location, and so on. The Project component is also used to specify certain project-specific settings such as the system of units to be used, global constants, finite element mesh settings and quality control procedures. For this example, the following information is stored in the general Project Settings dialog.
Table: General Project Settings
Property |
Value |
Project Title |
Example 9 - SCR Transfer |
Job Number |
1-2-3-342 |
Engineer(s) |
Wood PLC |
Location |
Galway |
In the case of this example, the default project-specific settings are used (e.g. metric unit system, default mesh settings etc.).
The Material component is used to define the physical properties associated with a particular material. There is only one material used in this project, steel with the properties given in the table below. The Material component is located in the Material folder and is named ‘Steel’ in this example.
Table: Material Properties for ‘Steel’
Property |
Value |
Young's Modulus |
207 GPa |
Shear Modulus |
79.9 GPa |
Poisson’s Ratio |
0.33 |
Mass Density |
7798.3 kg/m3 |
Coefficient of Expansion |
0 1/c |
Yield Strength |
448 MPa |
Allowable Stress |
100 % |
Allowable Strain |
0.25 % |
The Pipe Section component is used to specify the properties of an individual section of pipeline that has uniform properties. This example contains one Pipe Section component as follows:
▪The Pipe Section component is created in the Line folder and is named ‘24" Pipe’.
▪The specification is Standard.
▪The material used is ‘Steel’, as defined previously.
▪The geometrical and hydrodynamic properties are listed in the table below.
Table: Properties for ‘24’’ Pipe’
Property |
Value |
Outer Diameter |
609.6 mm |
Thickness |
30 mm |
Normal Drag |
1 |
Normal Inertia |
2 |
The Cable component is used to specify the properties of an individual section of cable that has uniform properties. It is similar to the Pipe Section component in many respects, though less complex, as no additional coatings or attachments may be specified. The same Cable component is used to model both winch cables as follows:
▪The Cable component is created in the Line folder and is named ‘Winch Cable’.
▪The Standard specification is selected and the material used is ‘Steel’, as defined previously.
▪A relatively low bending stiffness of 0.01 kNm² is explicitly defined.
▪The geometrical and hydrodynamic properties are listed in the table below.
Table: Properties for ‘Winch Cable’
Property |
Value |
Diameter |
100 mm |
Normal Drag |
1 |
Normal Inertia |
2 |
The Connection component is used to model arbitrary connections between two lines (e.g. pipe sections, cables, etc.). Three separate connection modelling options are available, namely, Free, Hinged and Clamped. In this example a Free connection, named ‘Winch Connection 2’, is used to join the winch cable from the TLP to the top of the SCR, which means there is no rotational restraint applied to the winch cable where it meets the SCR. The table below shows the physical properties of this connection.
Table: Properties for ‘Winch Connection 2’
Property |
Value |
Weight in Air |
2 kN |
Weight in Water |
1.75 kN |
Flex Joint components are typically used to specify the properties of flexible or articulated joints between connecting pipe sections or cables. In the case of this example a flex joint, named ‘Winch Connection 1’, is used to connect the winch cable from the installation vessel to the top of the SCR. The table below provides a summary of the properties for this flex joint.
Table: Properties for ‘Winch Connection 1’
Property |
Value |
Type |
Linear |
Length |
0.1 m |
Rotational Stiffness |
0 kNm/deg |
Weight in Air |
2 kN |
Weight in Water |
1.75 kN |
At this stage, enough components have been defined to allow for the specification of the pipeline stack-up, which is defined in a Line component named ‘Pipeline’. A summary of the pipeline stack-up is provided in the table below. A connection is also defined on the line at a distance of 1200 m from the start (i.e. at the top of the SCR). This connection is named ‘Winch Connection’ and the Connection component used corresponds to ‘Winch Connection 2’.
Table: Pipeline Stack-Up
Section |
Length |
24’’ SCR(1) |
1200 m |
Winch Connection 1(1) |
0.1 m |
Winch Cable(1) |
10 m |
Two Vessel components are created in the Vessel folder in order to model the installation vessel and the TLP (namely ‘Lay Vessel’ and ‘TLP’). The properties and overall dimensions of both vessels are summarised in the tables below.
Table: Properties of ‘Lay Vessel’
Property |
Value |
Length |
120 m |
Depth of Keel below Origin |
7.5 m |
Horizontal Offset from Origin |
0 m |
Create Solid Profile |
No |
Table: Properties of ‘TLP’
Property |
Value |
Height |
50 m |
Draft |
12 m |
Length |
80 m |
Width |
80 m |
Y Offset from Origin |
0 m |
Z Offset from Origin |
0 m |
Create Solid Profile |
No |
A single Seabed component is used in the analysis, named ‘Rigid Seabed’. The default properties of a rigid seabed, with a zero coefficient of friction in the longitudinal and transverse directions and a slope of zero degrees, are left unchanged.