You can now move onto the Installation Stages tab, as shown in the figure below.
Installation Stages Tab
For this example, the abandonment analysis will be analysed over 15 static stages. Each installation stage is identified by a unique stage number. This enables various parameters and criteria to be assigned to individual installation stages. Your first stage will be a simple static analysis of the model as you have built it. In order to define the first analysis stage, Stage Number should be 1, which it is by default.
As mentioned, this analysis is to be performed as a series of static stages and the Stage Type drop-down list can be left at its default value.
Pipelay contains a restart capability which allows you to restart an analysis stage from a previous analysis stage. In a restart analysis, the structure configuration at the end of the preceding analysis becomes the starting configuration for the restart. An example of this application might be running a random sea dynamic stage using the configuration solved for in a preceding static stage. This option is not required for this example so leave the Restart drop-down list at its default value of No. The Restart From drop-down list is disabled when you are not performing a restart.
As this is a static stage, time variables are irrelevant. The Time Step Type drop-down list and Time button are disabled and may be ignored.
The Current, Primary Wave and Secondary Wave drop-down lists may be ignored, as there is no current or wave loading considered in this static analysis.
There is no need to Transfer Adjustments from the criteria analysis of this static stage to any subsequent stages in the analysis (they will all have their own criteria anyways), so you can leave the associated drop-down list at its default value of No.
No customised postprocessing is required – the default automated postprocessing is sufficient – so you may also ignore the Custom Postprocessing drop-down list.
You have now fully defined the first installation stage. To add this stage to the list of analysis stages, simply click on the Add button. Note that an Automate Stages dialog will appear after clicking the Add button however it is not needed for the time being so simply click OK and it will disappear. Stage 1 is now added to the analysis as shown in the figure below.
It is worth noting that previously defined installation stages can be modified or deleted at any time. If you want to remove an existing installation stage from the analysis, just click on it in the list to select it and then click the Remove button or alternatively, all stages can be removed with the Remove All button. To update a stage, first select it in the list. You will see that all parameters on the tab are updated to those for the stage you have selected. Change those you need to modify and click on Update. The list will be updated accordingly. Note that some users may find the requirement to click on Update somewhat cumbersome, and even unnecessary. With this in mind, PipeLay also offers an alternative automatic update feature where the user interface automatically stores any changes made to an installation stage as soon as you click away from the stage in the list, for example if you click on a different stage in the list or indeed move to another tab. This automatic update is enabled by ticking the fourth box in the ‘Quality Section’ of the Project component.
Define Stage 2 in a similar fashion to the Stage 1. Note that all subsequent stages (3-15) can be generated after defining the parameters and criteria for Stage 2 using the Automate Stages dialog. This will be discussed later under the ‘Generate Subsequent Stages’ heading.