Date:         Sun, 10 Jul 2011 09:37:23 -0400
Reply-To:     Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject:      Re: [Friday] Bolts -- Rockwell hardness translate to grade?
Comments: To: David Beierl <dbeierl@attglobal.net>
In-Reply-To:  <4e188737.4f76e50a.29c9.ffffa648@mx.google.com>
Content-Type: text/plain; charset="US-ASCII"

Yes the ball is larger, 3/8. Have to stop answering thing when I should
sleeping. The kit we have uses a shear pin to drive the ball. Hit the tool
with the hammer and the pin breaks and the ball leaves the dent.

Dennis

-----Original Message-----
From: David Beierl [mailto:dbeierl@gmail.com] On Behalf Of David Beierl
Sent: Saturday, July 09, 2011 12:50 PM
To: Dennis Haynes
Cc: vanagon@GERRY.VANAGON.COM
Subject: Re: [Friday] Bolts -- Rockwell hardness translate to grade?

At 01:20 AM 7/9/2011, Dennis Haynes wrote:
>Brinell testing 60 pound ansi rails for automated storage-retrieval
>cranes. The 1/16" ball penetration test.

Rockwell and Brinell measurements differ in some fundamental ways.  Rockwell
measures the difference in penetration *depth* between a 10 kGf preload and
the working load of 60, 100 or 150 kGf.  The hardness number is read
directly from the machine's scale. T

Brinell applies a calibrated force  - unless otherwise stated the penetrator
is a 10 mm (fat 3/8") ball and the force is 3,000 kGf - and the *width* of
the indentation is measured by examining it through a microscope with a
calibrated graticule.  The Brinell number is obtained by formula or by use
of a table supplied with the machine.

Yours,
David