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There is no means of simply creating it if it is not there. You can restore it to your "templateless" file by opening a new Project with the Mechanical Template and using Transfer Project Standards (located on the Manage tab) to bring the "Pipe System Types" into your Project. This will bring them ALL over, including the "Other" Pipe System.
Corey D. ──────────────────────────────────────────────────────────────────────⁞|⁞ Please use .Accept as Solution and Give Kudos as appropriate to further enhance these forums. Thank you!