Marking Specification Changes
- Last UpdatedJul 27, 2025
- 1 minute read
The specification reference for a pipeline will appear in the bottom right-hand corner of the isometric drawing, immediately above the pipeline reference.
Pipeline specification changes are indicated by notes against the corresponding points on the isometric plot. By default, specification changes are noted at component level, but they can be noted at branch level by using the SPECBREAK command.
Whenever a specification change is shown on the drawing, both the original and new specifications at each change point are plotted. The format is similar to that used for dimensioning.
The format is illustrated in the Marking a change in pipeline specification image.
Insulation and tracing specification changes can also be shown.

Marking a change in pipeline specification
Whenever a change of specification is encountered in a pipeline, the information is recorded in the IDF file and a specification change label is output at the appropriate point on the drawing.
Ten types of specification change are catered for:
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Pipeline name (for system isometric only)
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Piping material specification
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Insulation specification
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Tracing specification
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Painting specification
A maximum of ten changes are allowed at a single point.