Adding to the Edge Preparation Catalog

Edge Preparation Characteristics

The main characteristics of a plate edge that is prepared for welding are shown below:

A root gap is the distance between two plates to be joined to improve penetration of weld and increase quality and strength of weld joints. The root gap can be considered as a negative margin that needs to be applied to the plate contour.

The figure below shows how the edge preparation characteristics of a joining activity could be shown during the interactive session.

Standard and User Defined Edge Preparations

Standard default edge preparation symbolic parametric sketches are provided in a catalog of User Defined Features (UDFs). It is found at the following location:
..\OS\startup\startup\FeatureCatalogs\Edge_Preparation.catalog

Here is a sample parametric sketch of a V Bevel edge preparation:

A quick way to create your own edge preparation UDFs is to start from an existing one. In any case, standard conventions must be respected:

• Symbolic parametric sketch must be created in positive H-Axis and V-axis. The sample sketch below represents a Double Bevel with Shoulder.
  
  
• Parametric sketch must contain at least the following driving parameters:
  • Thickness of plate or profile web is driven by a parameter called Thickness. This parameter drives two parallel straight lines representing top and bottom versus left and right faces according to position of plate or profile.
    Note that 3D representation of edge preparation is symbolic in the sense that top and bottom faces are shown as straight lines even if the plate is curved.
  • Root gap is driven by a parameter called Root_Gap. This parameter is measured from V-axis.
• Relevant parameters that drive edge preparation must be published.

You must set parameters that are to be displayed in 3D.

Edge Preparation UDFs

Edge preparation is described through a User Defined Feature exposing:

• parameters published by the administrator.
  These are either user defined parameters defining edge preparation geometry
  or conventional parameters for application purpose
• a parameterized sketch displaying the geometry of edge preparation.
  The sketch should be adequately constrained (elements displayed green). Be careful to not over-constrain the sketch (elements displayed violet).

A marking text is associated to the edge preparation. Its content is related to the Naming_Rule published parameter.

A negative margin is associated to the edge preparation. Its value is related to the Root_Gap value.

Displaying Parameters in 3D

Display the sketch constraint in Part.

Right click on constraint in tree and select Add Display.
Various display modes are available: value only, name only, both name and value, with or without a leader.

Published Parameters

Two kinds of parameters must be published:

• user defined parameters, which drive the edge preparation.
• conventional parameters for displaying thickness, associating a marking text, and positioning and orienting the edge preparation.
  There are naming rules for these parameters.

Marking Text Content Associated to Edge Preparation

Marking texts are specific to each shipyard. They have their own conventions to put information on the plate on shape. It is up to administrator to define the content of each text associated to edge preparation. This can be done either by creating new edge preparation UDFs or by editing each UDF part contained in the catalog and modifying the content of the Naming_Rule parameter.

Note that the content of the text for Single_Bevel is different from the other in the catalog as it demonstrates the capability to associate parameter value to the marking text.

Required Setting

To display the parameters and constraints of the UDFs, select the Parameters of features and constraints check box under the Display in Geometry Area that is part of the Part Infrastructure tab in Tools > Options > Infrastructure.

Edge Preparation Checking

You need to check that correct edge preparation configuration has been provided for performing welding process. As edge preparation activity is performed separately on each single plate or profile with a given workshop position, you must check that plates or shapes positioned together when they are welded do not show mismatches between their edge preparation.

Figure below shows mismatch between edge preparations at welding stage.

Figure below shows correct edge preparation configuration.

To check that a generated edge preparation is correct you can check the following points.

• Correct configuration at the butt joint. You have to use the IPM Navigator to go to the joining activity and then activate As lofted view check box and have a look at the butt-joint.
• Edge preparation has been created on the correct edge, at the correct location with correct orientation (molded vs. thick side)
• Root gap has been created with the right value if it has been requested (usually you can check that by looking at root-gap parameter)
• Edge preparation parameters are OK
• Associated marking text has been created with correct content on burn side up face, with right orientation, and so on.