joeysss
Mechanical
- Sep 11, 2006
- 2
I fully understand that TEMA is a guideline and it is not a design Code like the ASME Sec. VIII, but I would like to ask following question to TEMA committee and/or any heat exchanger expert concering the TEMA requirement for 1 1/2" diameter alloy tube gauge thickness.
The thinnest tube thickness allowed per TEMA Table RCB-2.21 for 1 1/2" alloy tube is 14 gauge. This is pretty straight forward except there is a statement in paragraph RCB-2.21 (directly above this table) which allows "other tube diameters & gauges" when the tube diameters are not common. The 1 1/2" diameter tube is a common size (versus 1 3/8" or 1 3/4" dia.) in USA which is readily available.
What does the last sentence in this TEMA paragraph RCB-2.21 mean? Does it mean like when there a metric tube sizes (like; DIN, JIS or 1 3/8" dia. tubes etc.) which are not common in USA and when they do not match the tube sizes shown in TEMA Table RCB-2.21? Is the 16 gauge thickness for 1 1/2" tube allowed per TEMA paragraph RCB-2.21 instead of 14 gauge per TEMA RCB-2.21?
To reduce confusion, I wished that this brief sentence in TEMA paragraph RCB-2.21 had stated; "unless noted otherwise (U.N.O.) in Table RCB-2.21, other tube diameters, and gages are acceptable". But it does not say U.N.O. therefore; I need your expert assistance to resolve TEMA ambiguity.
We specified TEMA on our MDS (Mechanical Data Sheets) which is part of our PO agreement, but one of the US fabricator is using 16 gauge thickness instead of 14 gauge for 1 1/2" alloy tube. Therefore, I am trying to solve following TEMA ambiguity and learn what TEMA intended:
1) Can the vendor ignore Table TEMA RCB-2.21 and use 16 gauge instead of 14 gauge?
2) What was the TEMA intent in showing all those tube sizes with choice of gauge thickness shown in Table TEMA RCB-2.21? (why did TEMA show this Table if it is a guidline?)
I will appreciate if anyone can further shed any light on above specific questions. Thank you in advance for your time and prompt response.
Regards.
Bart V. Makadia, P.E.
The thinnest tube thickness allowed per TEMA Table RCB-2.21 for 1 1/2" alloy tube is 14 gauge. This is pretty straight forward except there is a statement in paragraph RCB-2.21 (directly above this table) which allows "other tube diameters & gauges" when the tube diameters are not common. The 1 1/2" diameter tube is a common size (versus 1 3/8" or 1 3/4" dia.) in USA which is readily available.
What does the last sentence in this TEMA paragraph RCB-2.21 mean? Does it mean like when there a metric tube sizes (like; DIN, JIS or 1 3/8" dia. tubes etc.) which are not common in USA and when they do not match the tube sizes shown in TEMA Table RCB-2.21? Is the 16 gauge thickness for 1 1/2" tube allowed per TEMA paragraph RCB-2.21 instead of 14 gauge per TEMA RCB-2.21?
To reduce confusion, I wished that this brief sentence in TEMA paragraph RCB-2.21 had stated; "unless noted otherwise (U.N.O.) in Table RCB-2.21, other tube diameters, and gages are acceptable". But it does not say U.N.O. therefore; I need your expert assistance to resolve TEMA ambiguity.
We specified TEMA on our MDS (Mechanical Data Sheets) which is part of our PO agreement, but one of the US fabricator is using 16 gauge thickness instead of 14 gauge for 1 1/2" alloy tube. Therefore, I am trying to solve following TEMA ambiguity and learn what TEMA intended:
1) Can the vendor ignore Table TEMA RCB-2.21 and use 16 gauge instead of 14 gauge?
2) What was the TEMA intent in showing all those tube sizes with choice of gauge thickness shown in Table TEMA RCB-2.21? (why did TEMA show this Table if it is a guidline?)
I will appreciate if anyone can further shed any light on above specific questions. Thank you in advance for your time and prompt response.
Regards.
Bart V. Makadia, P.E.
