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RE: Welding Anchor Bolts

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The vast majority of anchor bolts (headed or hooked) are "fabricated" by the
structural steel fabricator or a subcontractor from A36 stock.  The testing
specified in A307 never happens because the lots are too small and the
fabricators generally do not have the testing facilities or budget.  The
reason for the slight increase in allowable stress in A307 versus A36
fabricated bolts is the testing.  The fabricated bolts are tested in A307. 
Only the material is tested in the A36 spec.
 
The certifications provided are seldom properly prepared and seldom
submitted.  The best way to avoid the issue is to make all mild steel anchor
bolts A36.  Another issue is the head.  Thread both ends and deform the
threads on the anchored end.  Avoid using hot headed bolts, because they
will be the weak link.
 
Spark testing is another method of determining my "old guy" status.  Spark
testing is a quick and dirty method of determining carbon content of
steels.  A grinder is used to strike a spark on the steel material. 
Experienced metallurgists and welders (other old guys) can determine carbon
contents by the length and brightness of the spark with remarkable
accuracy.  If you want to calibrate the "other old guy", you use PMI
(Positive Material Identification) device which can break down the
components for determining actual carbon equivalents.  Testing labs with a
good metallurgist will have these devices and others for determining steel
material components.
 
Harold Sprague
The Neenan Company 
harold.sprague(--nospam--at)neenan.com <mailto:harold.sprague(--nospam--at)neenan.com>  
 

-----Original Message-----
From: Robert Rollo [mailto:rrollo(--nospam--at)TEAM-PSC.com]
Sent: Monday, January 04, 1999 8:20 AM
To: 'seaint(--nospam--at)seaint.org'
Subject: RE: Welding Anchor Bolts



	harold, please expound on why not A307, are you not specified
correctly due to the: 

	"Specifically the A307 specification says "Nonheaded anchor bolts,
either 
straight or bent, to be used for structural purposes, shall conform to the 
requirements of Specification A 36 with ....", 

	? ? ? 



	-----Original Message----- 
From:   John W. Bryan [SMTP:jaybryan(--nospam--at)voicenet.com] 
Sent:   Monday, January 04, 1999 9:08 AM 
To:     seaint(--nospam--at)seaint.org 
Subject:        RE: Welding Anchor Bolts 

	Please educate me.  What is the "spark test" to determine carbon
content 
referred to in the message below? 

	-----Original Message----- 
From:   Harold Sprague [ mailto:harold.sprague(--nospam--at)neenan.com
<mailto:harold.sprague(--nospam--at)neenan.com> ] 
Sent:   Tuesday, December 29, 1998 10:01 PM 
To:     'seaint(--nospam--at)seaint.org' 
Subject:        RE: Welding Anchor Bolts 

	It is true that the A307 specification does not limit carbon
content, but 
anchor bolts of this type are generally manufactured from A36 stock which is

a low carbon steel.  Anchor bolts should never be specified as A307.  If you

push it you will find that few specified A307 "anchor bolts" will be truly 
A307. 

	Specifically the A307 specification says "Nonheaded anchor bolts,
either 
straight or bent, to be used for structural purposes, shall conform to the 
requirements of Specification A 36 with ...." 

	Even if the bolt is headed, anchor bolt lengths (and any bolt longer
than 
about 10") will generally prohibit mass production and will generally be hot

headed from A36 stock.  This is not a good practice either, but is another 
topic. 

	A spark test on the bolt and the nut can confirm carbon content and
will 
dictate the welding procedure.  Then you can use the Temple sticks to 
confirm preheat.  It would be best to minimize heat input to avoid damage to

the concrete.  It can be effectively welded by a good welder and a good 
procedure. 

	Regards, 
Harold Sprague 
The Neenan Company 
harold.sprague(--nospam--at)neenan.com <mailto:harold.sprague(--nospam--at)neenan.com>