Steve -
Although I explicitly asked in the RFQ for the manufacturer to confirm compliance of tied joints with B31.1, one supplier did not say that a tied joint would not meet B31.1, but only offered an externally pressurized joint to comply with B31.1. That response has made me "uneasy". A second manufacturer has not yet responded.
From: <a href="/group/PipingDesign/post?postID=jK6A9Wy9GVtAJfoLTiusIw550l1BnKnr-wXYmpyO6eN8pYKvm_rzztyzAIw89BFcCLv-Uj5XPh8EGNj_9RGMQyVf1BY6">PipingDesign@yahoogroups.com</a> [mailto:<a href="/group/PipingDesign/post?postID=jK6A9Wy9GVtAJfoLTiusIw550l1BnKnr-wXYmpyO6eN8pYKvm_rzztyzAIw89BFcCLv-Uj5XPh8EGNj_9RGMQyVf1BY6">PipingDesign@yahoogroups.com</a>] On
Behalf Of Steve McKenzie
Sent: Tuesday, September 11, 2007 7:31 PM
To: <a href="/group/PipingDesign/post?postID=jK6A9Wy9GVtAJfoLTiusIw550l1BnKnr-wXYmpyO6eN8pYKvm_rzztyzAIw89BFcCLv-Uj5XPh8EGNj_9RGMQyVf1BY6">PipingDesign@yahoogroups.com</a>
Subject: RE: FW: [PipingDesign] B31.1 Bellows XJts - Complete Disengagement
Hi Ken
I think the disengagement bit refers more to slip joints that to bellows. Some internally pressurised bellows have internal liners which could conceivably disengage if the bellows were overextended. Tie rods will prevent this happening. The thing with bellows is to prevent out of range deflections (in all directions), rather than disengagement.
I doubt if you'll find an interpretation as none appears necessary. You can get the supplier to provide the appropriate certification if you are
still uneasy.
Cheers
Steve
>From: "Ken Nisly-Nagele" <knislynagele@
<mailto:knislynagele%40applied-e-s.com> applied-e-s.com>
>Reply-To: PipingDesign@ <mailto:PipingDesign%40yahoogroups.com>
yahoogroups.com
>To: <PipingDesign@ <mailto:PipingDesign%40yahoogroups.com> yahoogroups.com>
>Subject: FW: [PipingDesign] B31.1 Bellows XJts - Complete Disengagement
>Date: Tue, 11 Sep 2007 17:06:49 -0400
>
>No comments on this?
>
>
>
>Too boring an issue? Too busy? Need I go to that "other" forum?
>
>
>
>Ken Nisly-Nagele
>
>Applied Engineering Services, Inc.
>
>Indianapolis, Indiana
>
>
> _____
>
>From: PipingDesign@ <mailto:PipingDesign%40yahoogroups.com> yahoogroups.com
[mailto:PipingDesign@ <mailto:PipingDesign%40yahoogroups.com>
yahoogroups.com] On
>Behalf Of Ken Nisly-Nagele
>Sent: Sunday, September 09, 2007 10:03 AM
>To: PipingDesign@ <mailto:PipingDesign%40yahoogroups.com> yahoogroups.com
>Subject: [PipingDesign] B31.1 Bellows XJts - Complete Disengagement
>
>
>
>B31.1 2006, para. 101.7.2, states "...corrugated bellows...may be used
>if...their design prevents the complete disengagement of working parts
>while
>in service."
>
>I have interpreted that to permit the use of an externally pressurized
>bellows joint in which there are plates at the end of the bellows which
>would prevent the joint from completely disengaging.
>
>Do tied universal bellows joints comply with this B31.1 requirement? Some
>recent code interpretations have not addressed this...are there older code
>interpretations that have?
>
>I have an outdoor (-20 to +110 Deg. F ambient range) application for
>saturated 250 psig steam. I have rarely installed bellows type joints, and
>in this application, a tie-rod universal joint would be an option to reduce
>anchor loads and "column" buckling. I want to be open minded to the use of
>this type joint (with Inconel 625 bellows) if it meets code. The client has
>already said bellow joints would be an acceptable option.
>
>Ken A. Nisly-Nagele, P.E.
>Mechanical Engineer
>Applied Engineering Services, Inc.
>Indianapolis, Indiana
>
>[Non-text portions of this message have been removed]
>
>
>
>
>
>
>[Non-text portions of this message have been removed]
>
[Non-text portions of this message have been removed] Received on Wed Sep 12 08:20:00 2007
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