Shrinkage Statement
- Last UpdatedDec 08, 2025
- 3 minute read
When welding together plates or welding profiles to a plate surface, the plate will shrink due to the heating. Especially for thin plates the shrinkage is not neglectable but might have to be compensated for. The system has functions to achieve this.
The SHRINKAGE statement is used to indicate that the shrinkage compensation shall be activated for a panel. The actual compensation will take place when the plate parts are created.
This means that the panel is always stored with its correct extensions, The amount of the compensation can be controlled in different ways:
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entirely under user control via the SHRINKAGE statement.
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entirely automatic from a user specific external table and from the thickness of the plate.
In this case, the main direction of the shrinkage is defined by the stiffeners. Stiffeners and seams along the main direction will add to the compensation as controlled by the shrinkage object.
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partly manually, partly automatically.
For further information, see below.
Syntax
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SHR[INKAGE] [, <line>] |
Description
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<line> |
The line defines a direction, perpendicular to which the main shrinkage takes place (normally parallel to the main stiffeners). |
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If undefined, the system will search for that direction from the stiffeners. |
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SHR, U = 1000, M1 ... ; |
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SHR, Y = 1500, M1 ... ; |
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When the line is perpendicular to any of the axes, only the appropriate keyword need be given, for example, |
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SHR, U, M1= ... ; |
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SHR, Y, M1= ... ; |
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M1 |
Compensation factor for stiffeners to be applied perpendicularly to the main direction, that means, normally perpendicularly to the main stiffeners. |
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<p_sti_fact>::= <number> |
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M2 |
Partition perpendicular to the main direction, that together with M1 is used to defined a compensation factor for stiffeners (see above). |
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<p_sti_part>::= <number> |
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M3 |
Used as M1 and M2 but valid in a direction along the main direction |
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If M3 is left out, then the compensation is calculated automatically. |
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M3 = 0 indicates that no compensation should be made along the main direction. |
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M5 |
As M1 and M2 but to be used for shrinkage caused by seams parallel to the main direction. |
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M6 |
For the automatic calculation of the compensation, it is necessary that the corresponding information can be found in the shrinkage object.
The image below illustrates the concepts above.
The main direction is normally defined by the stiffeners but may be given on a line.
M1/M2 and M5/M6 are valid perpendicularly to the main direction. M2 is normally the position between the stiffeners, M6 the partition between seams.
M3 and M4 are applied parallel to the main direction.
Remark
If stiffener arrangement is as in the image below, the partition between the stiffeners will be incorrectly calculated (=d). In such and similar cases, the partition should be set manually.
Examplex
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1. |
SHR,; The compensation is calculated entirely automatically. |
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2. |
SHR, V, M1=0.5, M2=700, M3=0, M5=0; These two statements give the same result. The shrinkage is parallel to the u-axis. Compensation only perpendicularly to the main direction and for stiffeners only. |
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3. |
SHR, M2=800, M3=0, M6=2500; In this case, there is compensation only perpendicularly to the main direction. This direction is calculated automatically and the compensation for each profile is defined by the shrinkage table and the plate thickness. Similarly, the compensation for each seam is fetched from the shrinkage object. |