If the low point is only enough to fill the conduit to full diameter a
shop Vac has more than enough power to blow it out. If the conduit is
sealed to the Shop Vac it can, or should blow out water over a ft deep
(12 inches).
I don't know what a shop vac will do, dead headed, but I would guess it
will hit close to 24 inches. My dust collector fan should easily hit 36
to 48 inches. It's on wheels and the bag could be removed giving direct
access to the exhaust. It does not depend on air throughput like the
shop Vacs do, so it could run deadheaded with no flow for an hour. In
an open pipe, without looking it up, I'd guess the air flow is in
thousands of CFM
I purchased mine locally, but it's similar to theirs. Mine is one that
uses two of the big bags that are 5 microns, yet will handle several
machines at once.
Look up dust collector systems in the Grizzly catalog, or on their
site. http://www.grizzly.com/
73
Roger (K8RI)
On 1/29/2016 Friday 1:42 AM, Jim Thomson wrote:
Date: Thu, 28 Jan 2016 16:26:53 -0500
From: "Roger (K8RI) on TT" <K8RI-on-TowerTalk@tm.net>
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Buried or Elevated
I installed a "pull rope, or messenger cable" when I installed the
conduit. No need for the exercise of blowing a cable through the pipe.
The rope is a bit over twice the conduit length. 4th photo from the
top on http://www.rogerhalstead.com/ham_files/cablebox.htm
73
Roger (K8RI)
## Buried PVC, like 3 or 4 or 5 inch....works most of the time, but it can
be a crap shoot.
After working at the the local telco for 34 years, I have seen it all..and
heard all the stories from
co-horts who worked outside all year round. Some would be dry as a bone after
years...and some
looked like you pumped one helluva lot of water into them. I have seen some
splice box tubs that
had to be pumped everytime they had to be worked on, and with lid removed, they
would be full to the
top with water, while others were dry.
## the other problem with water ingress..... depending on outside temps, and
frost line, water will freeze,
ice expands, then causes more problems, with pvc bursting or cracking..which
allows more water in come spring time.
Any coax or cables you stuff through the pvc should be able to be immersed in
water. The other issue is the pvc
settling at a low point, somewhere along its say 200 ft length. Get water in
there, and it will pool up at the low point..
then have fun trying to dry it out.
Jim VE7RF
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
--
73
Roger (K8RI)
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|