This is where the anchor spread is configured, including settings to store all anchor actions and anchor positions. It is also used in actual running of anchors, especially the Anchor Setup dialog, where anchors are assigned to tugs and actions such as 'drop' and 'pickup' are initiated. It is only available when a Tug Manager Output System has been added to the Database Setup. To see this option make sure to first enable 'Show Anchor Setup' in the Settings - Session Shortcuts menu.
Configure vessels and tugs which will be involved in the anchor procedures. Rig is a generic term that means any object from which anchors are deployed including a dredger.
Generate anchor positions based on the planned position of the barge.
Settings
Click on Settings to open the Anchors Settings dialog.
Make selections related to anchor actions/positions storage, and their presentation on the Navigation Display.
Anchor status and position are stored in an Anchor History log file. Drop and Pickup locations can also be stored in a *.qgf line database file, either the same database in which all main lines, routes and points are stored, or a dedicated database for anchor positions.
Positions may be stored with either UTC or local time, e.g
Picked up or
Dropped .
The addition of a sequential counter is optional.
Anchor icons and the 'rubber band' lines connecting objects can be displayed in different colors referenced to anchor status, i.e. Free, Racked, In Transit, or Dropped.
Anchor cable Catenary calculations are unlikely to be used in dredging operations.
Click on Rig and Tug Setup to open the Rig and Tug Settings dialog.
Make selections to define the Operation type.
Either the dredger itself deploys and recovers anchors (One Vessel, No Tugs), or one or more tug(s) are used to ferry anchors from the dredger (Multiple Vessels (Rig and Tugs)). Note that this selection can only be changed when no anchors are defined on the Anchor Setup page so make sure to remove any that are listed in that page.
Assign a winch node to each fairlead (a device to guide a line, rope or cable around an object, out of the way or to stop it from moving laterally). Make selections for the tug(s). Typically the Roller Node is the stern roller.
Click on Anchors Setup to open the Anchor Setup dialog in which anchors are added and configured.
This is also the page open when running anchors..
Initially the main pane is empty. Click on Add to create the first anchor. Click again to create a second anchor and so on.
Once anchors are added the main pane looks like this:
Setting
State
First assign a winch node to each anchor. Anchor State changes to .
Name
Next give each anchor a name.
Plan Location
Define where the anchors should be dropped. Planned locations may already exist in the line database file selected under Anchor Settings or can be Generated. If so select the appropriate planned locations. Alternatively enter location coordinates manually.
Radius 1 & 2
Two circles can be drawn around each anchor. Because they move along with the anchor when it is being re-positioned, they are useful in the Navigation Display when obstructions/hazards on the seabed must be avoided by certain distances. For example an anchor canot be dropped closer than 150m from a pipeline when the anchor is on the same side of the pipeline as the dredger, or 300m when the anchor is on the opposite side of the pipeline. In such a case set the radii at 150m and 300m.
Assign to
The next step is to assign a tug to an anchor. State changes to .
Action
The Action button becomes live, initially showing . Clicking on this button changes the state to , i.e. the anchor is on board the tug as it transits to the drop location.
Range markers may be set in the Navigation Display to show bearing and distance between winch and tug, winch to planned drop, and tug to planned drop.
Drop Location
This button becomes live and must be pressed when the tug drops the anchor, at which point state changes to .
Drop location coordinates are updated automatically.
Having completed the drop for one anchor, assign the tug to the second anchor. The dialog now looks like this:
Further picking up and dropping is a repetition of the above.
Parachute buoys are not normally used in dredging operations. Pennant wire lengths are not normally of concern either.
Please refer to the Navigation Display section for information about displaying anchors.
Click on Generate to open the Generate Planned Anchor Locations dialog.
Because this is a planning action, planned anchor locations are generated from a reference node.
Enter predefined coordinates, either in grid or geographical format. Typically the 'vessel' (object = dredger) also has a predefined heading.
Fairlead variable nodes specified in the Database Setup program are listed under Available Nodes.
These are usually the nodes from which the bearing and distance of anchor wires are measured. Generate uses the ranges and angles entered to compute anchor locations relative to these fairlead nodes. Angles used in the computation can be either absolute (referenced to north) or relative (referenced to the heading of the object entered above. By default anchor names are assigned to each available node. Change the names for any activated nodes.
Pressing Generate triggers a message box, something like this:
