PIAS Manual  2021
Program for the Integral Approach of Shipdesign
Crane loading tool
This tool is used for defining crane loads. Based on the predefined crane properties, the combined crane load and corresponding COG's are determined. This module for PIAS can be operated from a numerical input sheet, and from a Graphical User Interface (GUI) and for LOCOPIAS only from the GUI.

Note
A video exists in which the operation of this module is demonstrated.

Layout

Show and manipulate defined cranes and, if applicable, ballast tanks in a Graphical User Interface, an example of which is depicted below. A description of the labeled elements follows.

layout_crane_module840.png
Crane module GUI.
1 Menu bar

Basic functions are accessible through the menu bar.

2 Module buttons

These buttons navigate to another module, or back to the main screen.

3 Crane selection

Choose the crane you want to manipulate.

4 Cargo selection

From the drop-down box choose the cargo you want to load.

5 Crane operations

Use the buttons to steer the crane or manipulate cargo parameters.

6 Crane / Cargo operations

Enter values directly here.

7 Interval settings

Set interval step for meters and degrees.

8 Tank view

View on the (first) selected tank in a cross section.

9 List of tanks

Select a tank for ballasting. For transfer of tank contents between tanks change to the [Tanks] module 2.

10 Track bar

The track bar can change the filling of the selected tank.

11 Top view

The circles in the top view indicate the maximum and current radius of the crane for the upright vessel.

12 Cross section on active crane

In the cross section view the heeling angle and position of the crane can be seen.

13 Activity log

Opens a window on top, in which all crane and ballast operations are listed. This log can be printed. Reset empties the log.

14 Function buttons

Specific functions to operate the crane, manipulate cargo, pump tank contents and verification of the current loading condition.

15 Result windows

Direct verification of stability or strength. This dynamic repositionable window can be activated by the menu bar function [Window]→[Result windows].

16 Status bar
Shows information about the selected crane.

General

On startup of the crane module an input menu, as shown below, is displayed in which crane data can be entered. On exit of the crane module only the selected cranes are added to the list of weight items. During input of crane data a line with hydrostatic information can be displayed at the bottom of the screen. This hydrostatic data is valid for the loading condition including all selected cranes. It is possible to define a maximum of 10 different cranes.

loadingtools_crane_load_definition.png
Crane load definition.

In the example above, two boom cranes are defined. ‘***’ means a value cannot be determined currently.

Accidental loss/drop of crane load

If this extension has been purchased, the stability criteria which are applicable after the crane load accidentally drops out of the crane can be calculated. For this calculation you should pay attention to the following items:

  • The criteria as usually applicable for this vessel during crane operations should be selected.
  • A set of stability criteria as applicable after the drop of crane load must be defined and NOT selected.
  • The column ‘loss of load’ must be set to yes for this set of stability criteria.
  • Then, if a crane load item defined with the crane module with a weight > 0 is found, calculations for loss of crane load will be executed.
  • The loading condition will be calculated twice: first the situation with the load in the crane, secondly the situation without crane load.
  • If a requirement is defined including a ‘rollback angle’, the static angle of heel from the first calculation is used for the value of the rollback angle in the second calculation. This statical angle can be set via the variable ‘Heeling angle during lifting’, see Variables.

Menu bar functions

Config

A given set of crane definitions, positions and loads can be stored readily to include it in other loading conditions that use this option. Option [Config] gives an overview of all crane configurations. If a crane configuration is selected (with a ‘yes’ in the first column), the corresponding data will be used. Beware to give the crane configurations unique and unambiguous names, to avoid confusion later on.

Seagoing

Directly set cranes to position as defined (see Inputdata).

Inputdata

The following particulars define the crane and its position:

  1. Selected: Selected cranes will be included in the list of weight items when you leave the crane module.
  2. Name of this crane: The identification name for this crane.
  3. Crane load: The weight of the crane load in tonnes can be entered here.
  4. Slewing angle: Angle of the boom relative to the centreline of the ship. Angles to SB are positive.
  5. Topping angle: Angle of the boom relative to the base plane of the vessel. Angles upwards are positive.
  6. Jib angle related to boom.
  7. Longitudinal position crane load: Length of the point of application of the crane load from APP.
  8. Transverse position crane load: Breadth of the point of application of the crane load from CL.
  9. Longitudinal position of vertical rotation axis: The longitudinal distance from App of the vertical rotation axis of the crane.
  10. Transverse position of vertical rotation axis: The transverse distance from the centreline of the vertical rotation axis of the crane.
  11. Weight of part rotating round vertical axis: The weight in tonnes of the part that exclusively rotates around the vertical axis. The boom, for example, which also rotates around the horizontal axis is defined separately.
  12. LCG of rotating weight at slewing angle 0 related to vertical axis: The longitudinal distance from the vertical axis of rotation to the cog of weight of part rotating round vertical axis. Forward of the vertical axis is positive.
  13. TCG of rotating weight at slewing angle 0 related to vertical axis: The transverse distance from the vertical rotation axis of rotation to the cog of weight of part rotating round vertical axis. SB of the vertical axis is positive.
  14. VCG of rotating weight: The vertical distance from base to the cog of the weight of the part rotating round vertical axis.
  15. Distance between horizontal and vertical rotation axis (fore=+): The longitudinal distance between the vertical and the horizontal axis of rotation. The distance is positive if the horizontal axis is forward of the vertical axis.
  16. Vertical position of horizontal rotation axis: Vertical distance from baseline to the horizontal axis.
  17. Length of boom: Length of the boom of the crane.
  18. Weight of boom: The total weight of the boom.
  19. LCG boom related to horizontal rotation axis (fore=+): Position of the lcg of the boom measured along the boom from horizontal rotation axis.
  20. VCG boom related to horizontal rotation axis (up=+): Position of the vcg of the boom measured perpendicular to the boom from horizontal rotation axis.
  21. Jib length.
  22. Jib weight.
  23. LCG jib related to jib rotation axis.
  24. VCG jib related to jib rotation axis.
  25. Outreach in line with bulwark: The distance perpendicular to CL, measured from 1/2 B to the transverse position of the crane load.
  26. Outreach horizontally: The horizontal distance measured from the upper side of the bulwark to the transverse position of the load
  27. Height bulwark: The height of the bulwark, measured from baseline to top of the bulwark.
  28. Display crane load and weight separately: If set to ‘no’, the selected crane and its load will be included in the list of weight items as a single weight item. If set to ‘yes’, the weight is divided in two separate items: the weight of the crane itself and the load.
  29. Aft. boundary from vert. rotation axis (forward=+): Aft boundary for the purpose of the longitudinal strength calculation.
  30. Fore. boundary from vert. rotation axis (forward=+): Forward boundary for the purpose of the longitudinal strength calculation.
  31. Weight group number crane + load: Crane and crane load can be given the same or separate weight group numbers, depending on the wishes of the user.
  32. Weight group number crane: see item 31.
  33. Weight group number load: see item 31.
  34. Seagoing slewing angle: With the function ‘Seagoing’ from the toolbar or in the graphical interface the crane is positioned in position with a slewing angle as defined here.
  35. Seagoing topping angle: With the function ‘Seagoing’ from the toolbar or in the graphical interface the crane is positioned in position with a slewing angle as defined here

Note: when slewing and topping angle values are changed, longitudinal and transverse positions of cargo are calculated automatically. Vice versa if longitudinal or transverse position of cargo is altered.

loadingtools_crane_aft_top_view.png
Crane definition aft and top view.