Terminology on mechanical drawing
Terminology on mechanical drawing
(OP)
This is probably a simple question but Google and my colleagues haven't been much help so far:
A fairly large vessel, almost certainly clad with thermal insulation, has two dimensions shown for its diameter: one is a plain 13.8m, the other is slightly larger "15.9m T/T". What does the T/T suffix signify? The two dimensions clearly aren't I.D. and O.D. so I'm wondering if it is diameter over the thermal insulation, or the dimension or between ports? Or something else entirely? Would appreciate if someone could help me out!
A fairly large vessel, almost certainly clad with thermal insulation, has two dimensions shown for its diameter: one is a plain 13.8m, the other is slightly larger "15.9m T/T". What does the T/T suffix signify? The two dimensions clearly aren't I.D. and O.D. so I'm wondering if it is diameter over the thermal insulation, or the dimension or between ports? Or something else entirely? Would appreciate if someone could help me out!
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RE: Terminology on mechanical drawing
Sorry I couldn't help on this though. Do you have an example of this you can post so maybe we can through some guesses at you?
Matt Lorono
CAD Engineer/ECN Analyst
Silicon Valley, CA
Lorono's SolidWorks Resources
Co-moderator of Solidworks Yahoo! Group
and Mechnical.Engineering Yahoo! Group
RE: Terminology on mechanical drawing
It doesn't ring a bell here but I've never worked on boilers etc.
KENAT,
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RE: Terminology on mechanical drawing
t/t = "Tangent-to-Tangent".
This is the length of the straight side from one tangent line to the other tangent line.
RE: Terminology on mechanical drawing
Thank you all very much.
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If we learn from our mistakes I'm getting a great education!
RE: Terminology on mechanical drawing
It means "tangent to tangent" or the straight length of the vessel including the straight flange portions of the curved vessel heads.