Moreover, the engineer could specify Ron's solution up front. Doesn't help the
design-build jobs - but you as the contractor could offer it up front...in such
a way that makes you look like you're helping the customer, not just seeking a
means to get more money out of them (easy to say...).
Mark and Ron - You are so correct. Put the header in and be done. It is less
expensive in the long run.
John
John August Denhardt, P.E., FSFPE
Strickland Fire Protection Incorporated
5113 Berwyn Road
College Park, Maryland 20740
Office Telephone Number: 301-474-1136
Mobile Telephone
NFPA 13 and 24 only require the forward flow test. Maybe they could be changed
to require a means to forward flow test? Around here most BFP's are installed
at the property line so they are not in the FP contractor's scope.
Ron F
-Original Message-
From:
I think we're talking about the 25 test here and this is an ongoing deal.
When you find a system without means it is in the owner's interest to pay
for installing a header, which can be as little as dropping the system and
adding a couple of mech tees and hose valves to the FDC line, plus the cost
What exactly is the purpose of a forward flow test on a backflow preventer?
This is not required on other check valve devices such as alarm valves, riser
checks, water meters, etc. Has there been a history of problems that this seems
to solve?
Todd G Williams, PE
Fire Protection
Yes there has. These checks are designed to be opening and closing
regularly and to differing demands. Once they started being required of
sprinklers it was found that they didn't always operate as designed (if we
were sitting with a bunch of models open I could show you various pinch
points where
I believe tommy d could fill you in on a lot of local horror stories.
Sent from my iPhone
On Jun 3, 2013, at 10:24 AM, Todd - Work t...@fpdc.com wrote:
What exactly is the purpose of a forward flow test on a backflow preventer?
This is not required on other check valve devices such as alarm
Brad,
Part 1 - Gibberish. Pure and simple. The tables in NFPA 13 didn't
reduce the force and distance by half in their calculations. It
simply used the formula to calculate the maximum moment at the point of
the load for a simple beam, based on the maximum length of various pipe
sizes
This discussion is about the minority of systems right? Doesn't the 2 main
drain take care of most LH and OH?
Chris Cahill, PE*
Senior Fire Protection Engineer, Aviation Facilities Group
Burns McDonnell
8201 Norman Center Drive
Bloomington, MN 55437
Phone: 952.656.3652
Fax: 952.229.2923
Ken,
Sorry if I touched a nerve or upset you. I am nothing but a designer with a
trust issue; I simply do not trust anything in any code or standard until I
can explain it to myself like I'm 6 years old.
May I send you a spread sheet I made many years ago? It will allow you to
quickly calc the
NFPA 13 has stated for a couple of cycles that a means shall be provided to
forward flow test the BFP. Look at 8.17.4.6.1. Because Mr Greenman requested
it, I'll state it shall be the FLOW portion of system demand. It just says a
flow test at system demand. THe annex implies flow by
exactly. NFPA 14 gives a lot of detail on how to accomplish this set-up.
Using a relief valve is a big no-no. Dumping a bunch of water every time you
do a churn test (weekly for diesel and monthly for electric) is a bad thing
that is not allowed by NFPA 20.
Roland Huggins, PE - VP
NFPA 14 allow to control separate zones with a pressure reducing valve
Thank you,
Sean Roberts
4456 Campbell RD, Houston, TX 77041
713-896-9941
Fax 713-896-9945
Cell 713-206-8837
sean.robe...@wsfp.us
-Original Message-
From: Roland Huggins [mailto:rhugg...@firesprinkler.org]
Sent:
Thanks guys
Joe C. Powell
Pruett Ford Associates, Inc.
Consulting Engineers
1201 Broad Street, Suite 3A
Augusta, GA 30901
Ph: 706-722-3959
Fax: 706-724-5127
Email: jpow...@pruettford.com
-Original Message-
From: sprinklerforum-boun...@lists.firesprinkler.org
There's also a master pressure reducing valve assembly (contains 2 primary
PRV's, a smaller PRV to account for lower sprinkler testing flows, a by-pass
etc etc) for controlling a larger portion of the building and triggered by
having more than 2 hose connections downstream of the BFP.
Roland
Brad,
No, thank you for the offer on the spreadsheet, I have myown, and
thanks to some very patient structural engineers on the hanging and
bracing committee, and the Eighth Edition of the Manual of Steel
Construction, I have all the formulas I could ever need or use. And,
because I
Chris - the potential design flow for an ordinary hazard, group 2 system is 300
to 400 gpm. Can you get that from your 2 drain? How do you know what rate your
2 in. drain allows? Even if your system is designed to flow light hazard and
has a maximum design flow of 125 gpm, how do you measure
my gosh Ken, you appear to be almost as stubborn as i am... i like that!
i wrote:
section modulus is moment divided by stress. moment is half the force(lb)
times half the distance(in).
the force is the weight of the water-filled pipe plus 250. the distance is
4ab/a+b.
the stress is 15,000.
for
you calculate it just like flow from any other orifice open to the exterior.
The judgement part comes in for assigning a discharge coefficient and the exact
size for a threaded orifice.
This issue was the exact topic of an article in the May issue of Sprinkler Age.
It can be accessed from
Dear All,
For one floor of a highrise tower, there is normally one supervisory valve for
the sprinklers of that floor.
Traditionally a supervisory gate valve is used but an UL/FM supervisory
butterfly valve is also manufactured at a cheaper price.
Does NFPA regulate to use which type of valve
Hello Phong,
No There are many systems with butterfly (butterball) valves in them. Just as
long as it is supervised or locked open.
Monday, June 3, 2013, 9:10:36 PM, you wrote:
Dear All,
For one floor of a highrise tower, there is normally one
supervisory valve for the sprinklers of that
Sorry for the late chime in - I'm (theoretically) on vacation and don't have
NFPA 20 with me.
As already stated, the 20 yields to other standards that may incorporate a fire
pump into an approved water supply - 13, 14, 24, etc. Where 20 ends isn't
defined, but the discharge control valve
22 matches
Mail list logo
