Texas
Slam Dance! - New Valve Technology Eliminates Valve Slam
By: Megan Rapaduski Larson
System
operators have their work cut out for them when the pumping
applications deal with high head, surge tanks, or multiple pumps.
A North Texas Wastewater treatment plant was learning
this first hand. The North Texas utility serves four
cities, the largest having between 70,000 and 80,000 people.
It's
lift station contains four 8 in. vertical centrifugal sewage
pumps that feed a 600 ft. long, 48 in. diameter force main.
Online since 1987, the station was equipped with traditional
weight and lever air cushioned swing check valves .
“The
check valves were breaking down. We repaired them, but
they kept breaking internally. We were getting a lot
of water hammer. This station takes a lot of flow, so
it was hampering us. The station was down until we could
get parts in or have them machined,” said a system operator
for the plant.
The
existing valves, from multiple manufacturers, were unreliable
and it was difficult to find something to fit the unique circumstances
of a vertical application. The existing air-cushioned
swing check valves had to be rigged with additional external
springs and cables in an attempt to combat slamming.
The valves were closing hard, and a 1-year old replacement valve
had just broken a shaft pin. The installation was too
dynamic for an ordinary check valve. The tall vertical
run of pipe after the pumps created extremely fast flow reversals
and water hammer after power failure. The existing valves
had weighted levers with cables and springs anchored to the
floor which made for a dangerous situation
“This
is one of the biggest suppliers of water in North Texas and
the largest processor of wastewater,” noted John Bolender, President
of Valve and Equipment, Huffman TX, a manufacturer's representative.
“They came to me looking for replacement valves that
could replace slamming cushion swing check valves.”
Enter
the Val-Matic SURGEBUSTER! Check Valve. Specifically
engineered to handle high head applications, multiple pump systems,
and systems known to surge, the SURGEBUSTER was designed to
handle extreme applications.
The
SURGEBUSTER achieves a rapid closure through a short disc stroke
of 35° and still maintains a 100% flow area. What
makes the SURGEBUSTER unique is the patented Disc Accelerator,
the next generation in valve technology. The Disc Accelerator
is a precision formed stainless steel mechanism that closes
the disc rapidly, avoiding any slamming by flow reversal while
also allowing the disc to be stabilized under flow conditions.
The accelerator is fully enclosed and out of the flow
path. The valve fully meets ANSI/AWWA C508.
“When
they told me about their application, I suggested the Val-Matic
SURGEBUSTER. I knew they hadn't seen anything like it,”
said Mr. Bolender.
“We
saw the valve and thought it was a good design,” the system
operator explained.
The
SURGEBUSTER was installed in place of the traditional swing
check valve after a vertical elbow on the vertical discharge
of an 8” pump. The results were so quiet, the flow could
only be heard by placing your ear against the valve.
The only way to tell that there was flow through the valve was
by the top mounted valve indicator.
The
traditional weight and lever swing check valves are now being
phased out of the facility, and the Val-Matic SURGEBUSTER check
valve has proved to provide some unexpected benefits.
All SURGEBUSTER valves come with a fusion bonded epoxy coating
on both the interior and exterior of the valve which is highly
resistant to the corrosion sometimes associated with wastewater
applications. And, due to the fact that there is no external
weight and lever on the valve, the external moving hazard was
eliminated making for a safer working environment.
“We
were amazed at how quiet it was! After that we were pretty
much sold. Another valve went down and I replaced it
[with a SURGEBUSTER]. As the other 2 go down I will replace
those as well,” the system operator declared.
For
more information on the SURGEBUSTER and to view tests conducted
with the valve, contact valves@valmatic.com
. Copies of the test are currently available on CD-Rom,
DVD, and VHS.
PVF
Industry Rocked By Material Increases
By: Phillip O. Landon
The
pipe, valve and fittings industry is getting hit with some of
the highest material cost increases it has ever seen.
The cost of ductile and gray iron castings as well as steel
products has escalated significantly over the last several months.
There
are several drivers behind this.
- Cost
and availability of raw materials. Scrap
steel and coke are in rising demand with decreasing availability.
Scrap/Pig Iron has increased dramatically as the following
graph from metalprices.com illustrates:

Metalprices.com
commentary: HOT
Pig and scrap iron prices established in early February reached
new historical highs. #1 Heavy Melting Scrap sold to Korea for
$308/MT. Included in this price is freight to Korea
estimated to be $85/MT which is over three times the cost from
a year ago. These freight rates are trending higher. Current
pig iron prices quoted to USA consumers are in the low $340's
per GT delivered.
USA
scrap iron prices are now higher than export numbers from both
coasts.
Fuel
prices are rapidly rising effecting the cost of producing castings
as well as the cost of shipping them. Fuel increases are
also impacting the cost of shipping finish goods.
The
US government has bought significant amounts of available shipping
capacity to provide supplies to Iraq. The
decreased capacity has spurred price increases and surcharges.
Asia
in general and China specifically have turned inward to meet
their own needs. The growth in China has been compared
to the American Industrial Revolution. Once a major exporter
of steel, China is now cornering the market on scrap metals
and coke to meet their own internal needs. Russia and India
are doing the same to a lesser degree.
All
of these factors have converged to create a near panic in these
sectors. What customers thought was firm pricing is no
longer firm. Price increases are being issued as well
as surcharges. Raw material suppliers and steel companies
are providing a base price at time of order and telling customers
final pricing will be provided at time of shipment. With
the lack of capacity, companies are refusing orders for materials
higher than historical quantities.
This
is an unprecedented situation. Your patience and understanding
are appreciated as we at Val-Matic make every effort to minimize
the impact on our valued customers. Please do not hesitate
to contact us with questions or to discuss.
Further
information may be obtained from the following links:
http://www.usatoday.com/money/industries/manufacturing/2004-02-20-steel_x.htm
http://www.meps.co.uk/hnews.html
http://www.chicagotribune.com/business/chi-0403010110mar01,1,1186214.story
http://www.cleveland.com/search/index.ssf?/base/business/1077791716314950.xml?bxbiz
http://www.cleveland.com/search/index.ssf?/base/business/1078396444141821.xml?bxbiz
http://www.post-gazette.com/pg/04046/273262.stm
|