X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from smtp105.sbc.mail.mud.yahoo.com ([68.142.198.204] verified) by logan.com (CommuniGate Pro SMTP 5.1c.5) with SMTP id 1455041 for flyrotary@lancaironline.net; Wed, 11 Oct 2006 00:42:38 -0400 Received-SPF: none receiver=logan.com; client-ip=68.142.198.204; envelope-from=dcarter11@sbcglobal.net Received: (qmail 36724 invoked from network); 11 Oct 2006 04:42:17 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=sbcglobal.net; h=Received:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=jW53S3SmivHM0stPm960Ae6nGIW2Tgez/NGtW+cspTRUsGcuF2+YdmjrQHDbymybDun4/Ll3tG25xpboD+U/wb919zZcNrTdZjb3FDohcEHQ8nuQg5oW0CrYx/we17cf8TyYkvy/V5Dx5kSPSmVH3Op6ni0ZKrk5KEAkC++SBAs= ; Received: from unknown (HELO davidsdell8200) (dcarter11@sbcglobal.net@67.41.228.58 with login) by smtp105.sbc.mail.mud.yahoo.com with SMTP; 11 Oct 2006 04:42:16 -0000 Message-ID: <340d01c6ecef$9fdabfd0$0701a8c0@davidsdell8200> From: "David Carter" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Exhaust Update Date: Tue, 10 Oct 2006 22:42:13 -0600 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_340A_01C6ECBD.549E4370" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2962 This is a multi-part message in MIME format. ------=_NextPart_000_340A_01C6ECBD.549E4370 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable How does a welder weld the "inside" of an exhaust pipe joint? Seems = like a long reach with tip of a long welding rod and a woefully small = angle for touching the seam to electricaly weld it. David ----- Original Message -----=20 From: Al Gietzen=20 To: Rotary motors in aircraft=20 Sent: Tuesday, October 10, 2006 8:41 AM Subject: [FlyRotary] Re: Exhaust Update >Just a heads up - it looks like your new "header flange to pipe" = (picture 5) was welded on the >outside. I think that 'acceptable = practices' state that there should only be a tack weld on the >outside = and the actual structural weld should be on the inside. What does = everyone else say? In >any event be sure to keep an eye on the welds. > >Ken Powell=20 It depends on the configuration. Generally, if are side loads due to = thermal stress, vibration, whatever; it is better to have a snug fit of = tube through the flange and weld on the inside. This reduces the stress = on the weld and can increase the reliability of the weld. The key in = either case is the quality of the weld and the heat treatment after the = weld. At least that's what I recall from my days as a practicing engineer. = Mine are welded on both sides. I'd prefer they were welded inside only. Al ------=_NextPart_000_340A_01C6ECBD.549E4370 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
How does a welder weld the "inside" of = an exhaust=20 pipe joint?  Seems like a long reach with tip of a long welding rod = and a=20 woefully small angle for touching the seam to electricaly weld = it.
 
David
----- Original Message -----
From:=20 Al = Gietzen=20
Sent: Tuesday, October 10, 2006 = 8:41=20 AM
Subject: [FlyRotary] Re: = Exhaust=20 Update

 

>Just a heads = up - it=20 looks like your new "header flange to pipe" (picture 5) was = welded on the=20 >outside.  I=20 think that 'acceptable practices' state that there should only be a = tack weld=20 on the >outside=20 and the actual structural weld should be on the inside.  What = does=20 everyone else say?   In >any event be sure to keep an = eye on the=20 welds.

>
>Ken Powell =

It = depends on the=20 configuration.  Generally, if are side loads due to thermal = stress,=20 vibration, whatever; it is better to have a snug fit of tube through = the=20 flange and weld on the inside.  This reduces the stress on the = weld and=20 can increase the reliability of the weld.  The key in either case = is the=20 quality of the weld and the heat treatment after the = weld.

 

At least = that=92s=20 what I recall from my days as a practicing engineer.  Mine are = welded on=20 both sides.  I=92d prefer they were welded inside = only.

 

Al

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