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The sheave is the "pulley", not the wire rope.<br>
<br>
<div class="moz-cite-prefix">On 2/27/2017 3:17 PM, Amrit Yegneswaran
wrote:<br>
</div>
<blockquote
cite="mid:575312605.742994.1488226663873.JavaMail.zimbra@jlab.org"
type="cite">
<div style="font-family: tahoma,new york,times,serif; font-size:
14pt; color: #009900">
<div>hi george,<br>
</div>
<div>my understanding is that a 7x19 cable is used.<br
data-mce-bogus="1">
</div>
<div>the breaking load for this cable, as per the manual, is
5559 Kg, much greater than 2x the tension (1550 Kg)<br
data-mce-bogus="1">
</div>
<div>amrit<br data-mce-bogus="1">
</div>
<div><img moz-do-not-send="true" class="shrinkToFit"
alt="http://www.bergencable.com/technology/images/7x19str.jpg"
src="http://www.bergencable.com/technology/images/7x19str.jpg"
data-mce-src="http://www.bergencable.com/technology/images/7x19str.jpg"
height="398" width="498"></div>
<div><br data-mce-bogus="1">
</div>
<div><br>
</div>
<hr id="zwchr" data-marker="__DIVIDER__">
<div data-marker="__HEADERS__"><b>From: </b>"George Jacobs"
<a class="moz-txt-link-rfc2396E" href="mailto:jacobsg@jlab.org"><jacobsg@jlab.org></a><br>
<b>To: </b>"Marco Mirazita"
<a class="moz-txt-link-rfc2396E" href="mailto:Marco.Mirazita@lnf.infn.it"><Marco.Mirazita@lnf.infn.it></a>, "Tyler Lemon"
<a class="moz-txt-link-rfc2396E" href="mailto:tlemon@jlab.org"><tlemon@jlab.org></a><br>
<b>Cc: </b>"dsg-rich" <a class="moz-txt-link-rfc2396E" href="mailto:dsg-rich@jlab.org"><dsg-rich@jlab.org></a>, "Bob Miller"
<a class="moz-txt-link-rfc2396E" href="mailto:rmiller@jlab.org"><rmiller@jlab.org></a><br>
<b>Sent: </b>Monday, February 27, 2017 1:33:59 PM<br>
<b>Subject: </b>Re: [Dsg-rich] RICH assembly<br>
</div>
<div><br>
</div>
<div data-marker="__QUOTED_TEXT__">What are the calculations on
the wire rope sheave? Looks to me it's overloaded as it will
see nearly 2X the wire rope tension as it's total load.<br>
<br>
George<br>
<br>
<div class="moz-cite-prefix">On 2/22/2017 10:34 AM, Marco
Mirazita wrote:<br>
</div>
<blockquote
cite="mid:0993815e72ea3080dfd89d8fcfb8797a@webmail.lnf.infn.it">Hi
all, <br>
here we try to answer to the questions raised in the last
couple of days on the RICH assembly. <br>
<br>
1) Winch load <br>
The weight of the RICH fully assembled is about 1000 kg,
including the stiffening elements. This would be the number
to be consider if we had to lift the RICH from the floor
with the winch. <br>
Instead, we want to use the winch to rotate the RICH on top
of the assembly structure. Thus, the maximum pull force that
the winch must apply has to be calculated in this
conditions. This has been done time ago, as you can see in
the two attached slides. The resulting maximum pull force is
about 7750 N, with a 25% safety margin we reach 9700 N, that
is a weight of 990 kg, lower than 1000 kg. <br>
The procedure for the load test should be defined based on
the foreseen usage of the winch. <br>
<br>
2) Eye bolt <br>
We agree to use the hoist ring as suggested by George. The
depth of the threaded hole in the aluminum angular element
of the RICH is 50 mm. The bolt is screwed to the RICH
passing through the bar of the stiffening element, which is
10 mm thick, 15 mm if we consider also the washers. We need
to screw the M24 bolt at least for a depth of 35 mm in order
to have a grade 8 connection. Thus the bolt should be at
least 35+15=50 mm. <br>
If JLab can provide them, it would be great. <br>
<br>
3) Assembly structure <br>
We thank DSG to have volunteered to continue the assembly of
the structures. We agree that the early completion of the
assembly will save time for the many other tasks we have to
do, so please go on. We suggest you to perform a preliminary
planarity check of the base plates before mounting the
vertical posts. A final alignment check of the structure can
be done when Dario and Sandro will be at JLab on march 6,
and then you can proceed together with the assembly of the
rotation elements. Please don't hesitate to contact us in
case of doubts or troubles. <br>
<br>
4) Documentation <br>
We are preparing the documentation for the assembly
procedure of the electronic panel support. We will also
include the description of the mechanical assembly of the
boards on the panel. <br>
The assembly of the mirrors will not be done before few
months. In addition, we planned in the next weeks a test of
the assembly of the aerogel on the planar mirrors. The
results of these tests may impact the procedure of the
mirror assembly, thus we will work on the procedure
documentation after these tests. <br>
For the electronics tests, it is up to the electronic group.
<br>
<br>
Dario, Marco, Sandro, Vincenzo <br>
<br>
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<br>
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</blockquote>
<br>
<pre class="moz-signature">--
George Jacobs
Jefferson Lab (TJNAF)
STE 12
12000 Jefferson Ave.
Newport News, VA 23606
(office) 757-269-7115
(cell) 757-876-0480
(email) <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:jacobsg@jlab.org" target="_blank" data-mce-href="mailto:jacobsg@jlab.org">jacobsg@jlab.org</a>
(website) <a moz-do-not-send="true" class="moz-txt-link-freetext" href="https://userweb.jlab.org/%7Ejacobsg" target="_blank" data-mce-href="https://userweb.jlab.org/~jacobsg">https://userweb.jlab.org/~jacobsg</a>
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<br>
<pre class="moz-signature" cols="72">--
George Jacobs
Jefferson Lab (TJNAF)
STE 12
12000 Jefferson Ave.
Newport News, VA 23606
(office) 757-269-7115
(cell) 757-876-0480
(email) <a class="moz-txt-link-abbreviated" href="mailto:jacobsg@jlab.org">jacobsg@jlab.org</a>
(website) <a class="moz-txt-link-freetext" href="https://userweb.jlab.org/~jacobsg">https://userweb.jlab.org/~jacobsg</a></pre>
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