<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body text="#000000" bgcolor="#FFFFFF">
Hello Pradeep,<br>
<br>
We use mostly dry pumps but the few wet pumps we have we use a
Fomblin type oil and soft start vacuum valves like this one from VAT
(<a class="moz-txt-link-freetext" href="http://www.vatvalve.com/business/valves/catalog/H/311_1_A">http://www.vatvalve.com/business/valves/catalog/H/311_1_A</a>). The
soft start valve helps to minimize the rush of oil back streaming
when pumping down chambers from atmosphere and is a little more
gentler on pumps. We have not seen an effect in ultimate pressure,
but pump down times are extended due to the added restriction in the
conductance.<br>
<br>
I highly recommend a dry roughing pump on the cryopump for
regenerating. The 15K charcoal array in the cryo pump can absorb
pump oil and decrease the cryo pump efficiency over time, which will
increase the frequency for regens and increase down time.<br>
<br>
Best Regards,<br>
Brent<br>
<div class="moz-signature">-- <br>
Brent P. Gila, PhD.<br>
Director, Nanoscale Research Facility<br>
1041 Center Drive<br>
University of Florida<br>
Gainesville, Florida 32611<br>
<a class="moz-txt-link-freetext" href="Tel:352-273-2245">Tel:352-273-2245</a><br>
Fax:352-846-2877<br>
<a class="moz-txt-link-abbreviated" href="mailto:email:bgila@ufl.edu">email:bgila@ufl.edu</a><br>
</div>
<br>
<br>
<br>
<div class="moz-cite-prefix">On 11/4/2019 5:39 AM, April, Mark R.
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:50a89d4aca8e4305bc20d69cbce040a9@draper.com">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta name="Generator" content="Microsoft Word 15 (filtered
medium)">
<!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]-->
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Cambria;
panose-1:2 4 5 3 5 4 6 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman",serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
p.msonormal0, li.msonormal0, div.msonormal0
{mso-style-name:msonormal;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:12.0pt;
font-family:"Times New Roman",serif;}
span.EmailStyle18
{mso-style-type:personal-reply;
color:black;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
<div><span
style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#FA4616"><b>[External
Email]</b></span>
</div>
<table width="100%" cellspacing="0" cellpadding="0" border="0"
align="left">
</table>
<div>
<div class="WordSection1">
<p class="MsoNormal"><span style="color:black">Good Morning <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">I only use Dry
pumps in my clean room at Draper.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">I removed all
of the oil pumps several years ago<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">Thanks<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span
style="font-size:9.0pt;font-family:"Calibri",sans-serif;color:black">Mark
R. April<o:p></o:p></span></b></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black"><img
style="width:2.3854in;height:.1458in"
id="Picture_x0020_1"
src="cid:part1.1184645E.C6D757BA@ufl.edu"
alt="https://intranet.draper.com/pcweb/media/branding/images/logo_styles/color_logo.jpg"
class="" width="229" height="14"></span><span
style="font-size:8.0pt;font-family:"Cambria",serif;color:black"><br>
</span><span
style="font-size:9.0pt;font-family:"Calibri",sans-serif;color:black">Senior
Equipment Engineer<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:9.0pt;font-family:"Calibri",sans-serif;color:black">Microfabrication
Laboratory Lead<br>
<i>555 Technology Square<o:p></o:p></i></span></p>
<p class="MsoNormal"><i><span
style="font-size:9.0pt;font-family:"Calibri",sans-serif;color:black">Cambridge,
MA 02139<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span
style="font-size:9.0pt;font-family:"Calibri",sans-serif;color:black"><a
href="mailto:mapril@draper.com" moz-do-not-send="true"><span
style="color:#0563C1">mapril@draper.com</span></a>
<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span
style="font-size:9.0pt;font-family:"Calibri",sans-serif;color:black">O
# 617-258-1613 C # 617-455-1596<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span
style="font-size:9.0pt;font-family:"Calibri",sans-serif;color:black"><a
href="https://urldefense.proofpoint.com/v2/url?u=http-3A__www.draper.com_&d=DwMGaQ&c=sJ6xIWYx-zLMB3EPkvcnVg&r=gl_2fLZA_-_JfH_dOmx7ug&m=r5rIOAO6mwwu499DOGlm3KInSe3pP9iF64SaEDshfYA&s=U7_XM5G7vQHo7qxnxkDRKLkxbuLtXxJLeyVB6n0UjUk&e="
moz-do-not-send="true"><span style="color:#0563C1">www.draper.com</span></a></span></i><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span
style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<a class="moz-txt-link-abbreviated" href="mailto:labnetwork-bounces@mtl.mit.edu">labnetwork-bounces@mtl.mit.edu</a>
<a class="moz-txt-link-rfc2396E" href="mailto:labnetwork-bounces@mtl.mit.edu"><labnetwork-bounces@mtl.mit.edu></a>
<b>On Behalf Of </b>Pradeep Nyaupane<br>
<b>Sent:</b> Sunday, November 3, 2019 8:21 AM<br>
<b>To:</b> <a class="moz-txt-link-abbreviated" href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a><br>
<b>Subject:</b> [labnetwork] Backing Vacuum Pump - Dry
pumps vs Oil Pumps<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<div>
<div>
<p class="MsoNormal">Dear All,<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal"> We have been using Dry pumps for
turbo pump backing for Sputters, E-beam evaporators.
And are planning to swap to oil pump with an anti-suck
back valve, whenever required (in case dry pumps go
bad).<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">We would like to know whether any
of you are using oil pumps are being used as backing
pump for Turbo / Cryo / DP.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Any advice / suggestions would be
greatly appreciated.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Thank You in advance.<o:p></o:p></p>
</div>
<div>
<div>
<div>
<div>
<div>
<div>
<div>
<div>
<p class="MsoNormal"><br>
<span
style="font-family:"Arial",sans-serif;color:#222222;background:white">Thanks
& Regards,</span><span
style="font-family:"Arial",sans-serif;color:#222222"><br>
<span style="background:white">Pradeep
Nyaupane</span><br>
<br>
<span style="background:white">Technical
Superintendent,</span></span><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Equipment Maintenance
Team In-charge, <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">IITBNF, <span
style="font-family:"Arial",sans-serif;color:#222222;background:white">Electrical
Engg Dept </span><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-family:"Arial",sans-serif;color:#222222;background:white">IIT
Bombay, India</span><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span
style="font-family:"Arial",sans-serif;color:#222222;background:white">Tel
No. 02225764471(O)</span><o:p></o:p></p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<hr>
Notice: This email and any attachments may contain proprietary
(Draper non-public) and/or export-controlled information of
Draper. If you are not the intended recipient of this email,
please immediately notify the sender by replying to this email
and immediately destroy all copies of this email.
<hr>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
labnetwork mailing list
<a class="moz-txt-link-abbreviated" href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a>
<a class="moz-txt-link-freetext" href="https://urldefense.proofpoint.com/v2/url?u=https-3A__mtl.mit.edu_mailman_listinfo.cgi_labnetwork&d=DwICAg&c=sJ6xIWYx-zLMB3EPkvcnVg&r=gl_2fLZA_-_JfH_dOmx7ug&m=r5rIOAO6mwwu499DOGlm3KInSe3pP9iF64SaEDshfYA&s=-w3DLimaT2XywZG8S4xth595hMvyNcFtINhPI6ZvaUw&e=">https://urldefense.proofpoint.com/v2/url?u=https-3A__mtl.mit.edu_mailman_listinfo.cgi_labnetwork&d=DwICAg&c=sJ6xIWYx-zLMB3EPkvcnVg&r=gl_2fLZA_-_JfH_dOmx7ug&m=r5rIOAO6mwwu499DOGlm3KInSe3pP9iF64SaEDshfYA&s=-w3DLimaT2XywZG8S4xth595hMvyNcFtINhPI6ZvaUw&e=</a>
</pre>
</blockquote>
<br>
</body>
</html>