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» PHCo News
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Perform Simple Electric Heat Maintenance
Asphalt Pro Magazine, November 2009
Process Heating Co., Seattle, Wash., specializes in low watt
density, dry well style immersion heaters for heating temperature-sensitive
products. For the asphalt industry, this means the manufacturer can provide a
heating system where low watt density elements keep the sheath temperature
decreased, reducing damage to the liquid asphalt cement (AC) and keeping
build-up/coking to a minimum in both asphalt tanks and hot oil systems. The dry
well design allows personnel to remove and perform maintenance on the heating
elements without draining the tank they're heating, according to Rick Jay,
Process Heating president. An intriguing aspect to the electric heating
elements that Jay pointed out is the lack of moving or wear parts, making
maintenance a simple issue. "Dry wells are heavy gauge steel pipe or tubing
for industrial duty, "Jay said."An annual electrical 'check up' is
all that is needed. Service personnel need to check for electrical operation,
test fuses and tighten connections. Many customers' forget we are there' instead
of having our parts department on their speed dial." That doesn't mean Jay
lets customers forget about regular maintenance. From good operation best
practices to proper maintenance, Process Heating Co. offers clients a manual
full of practical guidelines. Jay highlighted some of the points not to be
missed. For instance, when operating electric heaters, personnel should set the
indicating temperature control to the desired process temperature. The high
limit control for process temperature sensing will disconnect power to the
heaters if an "over-temperature" occurs. The high limit setpoint
should be approximately 20 to 25 degrees F above the process temperature. When
the temperature returns to below the high limit setpoint, the power will return
to the heating circuit, which allows the heaters to come on. However, a red
high-limit reset pushbutton will stay illuminated until personnel manually
reset it. This indicates to personnel that there was a high-limit occurrence,
allowing them to investigate the cause. Some of the reasons for an
over-temperature include:
•
a thermocouple failure on the main temperature
controller;
•
"over ranging" of the main temperature;
•
temperature controller setting is higher than the
hi-limit controller setting;
•
the main temperature controller is out of calibration;
•
the hi-limit controller is out of calibration; or
•
the heater magnetic contactor is locked in the closed
position because of "welded" contacts or mechanical binding.
The way to keep electric heating elements in tip top shape
and to avoid over-temperatures is to perform regularly scheduled maintenance.
Jay called attention to the following steps for best maintenance practices.
•
Periodically check all wiring connections in the
electrical control panel to be sure they are tight and free of oxidation.
•
Periodically check contacts on the contactors for wear.
Replace any contactor that is worn.
•
The tank interior should be cleaned at regular
intervals.
•
Check the tank's insulation regularly. Insulation tends
to break down over time, thus costing dollars in lost efficiency.
Not every plant takes advantage of electric heat, but those
that do have an opportunity to enhance this element's efficiency through basic,
routine maintenance. With professionals such as the engineers at Process
Heating Co., plant personnel have an industry partner to turn to for guidance
in this simple arena.
For more information, contact Rick Jay at Process Heating at
(866)682-1582 or visit www. processheating.com.
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A Hot Solution - F & R Asphalt beats fuel prices by adding an electric heater to its asphalt plant
Asphalt Contractor April/May 2009
 When fuel prices skyrocketed in the summer of 2008, many
asphalt plants were scrambling for a solution to keep down diesel costs. F
& R Asphalt, headquarted in Easley, SC, found one solution that did just that. F & R Asphalt
produces between 500,000 and 800,000 tons of mix a year; the majority is used
for DOT projects with some for commercial uses.
In the summer of 2008, when diesel costs were running toward $4 a
gallon, F & R decided to add a Process Heating Co. (PHCo) electric hot oil
heater at its Gray Court, SC facility, which produces about 200,000 tons of asphalt
annually. "We replumbed the unit ourselves," says Chris
Faucett, plant operator with F
& R. "It wasn't a difficult
installation; it probably took about three days." adding the
electric heater to the tanks when fuel prices were so high cut the cost to heat
the asphalt nearly in half, says Faucett.
Rick Jay, president of PHCo, runs the
numbers for an average plant: "fairly common size drum mix asphalt plant
will require a 140kW heater," he explains.
"This is adequate for two 30,000-gallon asphalt tanks and
associated jacketed pumps, meters and
asphalt lines. "For an asphalt plant using 75 gallons/day in the summer
and 100 gallons/day in the winter — with diesel at a cost of
$3.70, like it was in the summer
of 2008 — the fuel cost would be $277/day in summer and $370/day in
winter. "The electric cost is about
$0.11/KW — which is typical, and even lower rates can be
achieved using off peak hours and by controlling demand — so
with a 140kW heater running around 4
hours/day (summer) and 6 hours/day (winter), the electric cost would be $62/day
(summer) and $92/day (winter)."
Best of both worlds at F & R, the plant still maintains
its diesel-fired heater
as well as the
electric, so the plant can switch back and
forth between the
two, depending on
which system will
reap the most cost savings. "We
have both heaters in place," says Faucett.
"We installed the electric when fuel was nearly $4 a gallon. But we have the option to go back to the
electric if fuel prices start creeping up again." F & R has installed
a second electric heater at its Easley plant, which was just getting ready to
go on line at this printing. Faucett has high expectations for the heater. "I feel it will have similar
results," he says. "Our
Gray's Court unit has been running for six months and we've had no
problems. An electric heater
is more dependable and there's definitely less maintenance than with a diesel-fired
system."
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Tubular Heaters Maintain Oil Temperatures During Downtime Or Prior To Startup
TAPPI Journal, May 2001
Process Heating Co., based in Seattle, WA., has developed
rigid tubular heaters. These heaters are used as part of a paper machine lube oil system and in hydraulic reservoirs to maintain oil temperatures during downtimes for maintenance or to increase oil temperatures to a workable point prior to startup.
The heaters can be installed as new or as replacement equipment for existing Calrod-style tubular units; the Calrod units are of higher-watt density and can result in oil choking. Process Heating's
rigid heaters allow ease of replacement; they do not require machine downtime when being replaced. Furthermore, time-consuming oil draining is not required, and the heaters' low-watt density protects oil from damage. Rigid units of this design allow the heating elements to be equally spaced across the base of the reservoir for even heat distribution.
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Heavy Duty Drywell Heaters and Replacement Elements
Process Heating, June 2000
Lo-Density---A Big Plus The large heater surface area is designed with a predetermined low watt density (watts/sq.in.), giving low sheath temperature to avoid choking, buildup or material damage. Elements are ETL-listed and carry a five-year warranty. Tubes utilize 3" schedule 40 black iron pipe, but 2" and 4" sizes are available as well as other sheath materials including stainless steel and Inconel. UL-listed control panels are standard. Replacement
pipe insert elements, 2' to 40' can be custom sized and match both heating requirements and tank dimensions with single or three phase elements. Constructed of nickel chromium alloy coils, they have patented ceramic insulators. Elements can be flexed to a minimum radius of 24" in confined areas. PHCo elements are for new applications or replacing existing pipe insert elements.
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Cities Step up Efficiency
Reprinted from Asphalt Contractor Magazine
December 2000
Maintenance programs get a boost from
patching machine.
When it comes to street maintenance, the old fashioned method of taking a truck full of hot mix and a shovel out to patch a pothole seems to be losing popularity. From the truck-size pothole patching units to
trailers and boxes that fit existing equipment, crews find that efficient maintenance programs keep the complaint line form ringing off the wall.
Besides keeping mix hot and workers safe, dumping old pothole patching methods also increases the efficiency of the maintenance crews for the cities to be mentioned here. Each has its own pavement maintenance program, but all incorporate comments from the motoring public. To keep those customers from constantly ringing the phone, crews have to be quick about their work.
In the City of Savage, Minn., the Street Preservation Program focuses on a set 6 or 7 miles (9.7 or 11.3km) of city streets each year, according to Frank Gaillard, assistant public works director for the city. He explains that the maintenance work on those miles includes milling, overlays, pothole patching, and curb and gutter repairs, among others. One of the city's other programs involves a twice-yearly street-sweeping program. "Especially in the early spring," says Gaillard. "When you've got all salt-sand on the road, our street foreman goes behind the sweepers and makes notes of all the potholes in the city and develops an early list." Gaillard points out two benefits of this program. "The streets are clean right off the bat, and we can get them repaired before the phones start ringing."
Gaillard explains that crews used to perform pothole patching with the truck bed full of mix and a man with a shovel. About three years ago, the city purchased an electric asphalt-paving unit from Process Heating Co. Inc., Seattle. Now the crews can confine the mix in the heated box of the Patch King and can deploy the material via an augering system in the bottom of the unit.
Maintenance crews in the City of West Allis also use on of these units, but have a different maintenance program set up for finding the potholes to be repaired. Gordy Paprocki, with the City of West Allis, explains that the maintenance programs in his area incorporate official and public inspectors. "We do have a regular maintenance program where a couple of asphalt patch units are out on the street throughout the year, taking care of those issues," says Paprocki. The city also has street department supervisors who are in charger of watching out for potholes and other maintenance items. "Also, the public is encouraged to call the public works yard if they spot some nasty potholes that need to be taken care of."
The City of Louisville also encourages the public to call in to a pothole hotline when they encounter a problem. "As the calls or complaints are received about potholes, they are filtered through our system and the streets and roads division of the public works department," says Chester Denny, equipment procurement analyst for the City of Louisville. "They (public works department) assign the work."
Denny explains that there is a crew assigned to each of the automatic wards (districts) in the City of Louisville, and each crew has its own Patch King unit. "We use one truck in each ward, and its responsibility is to fix the potholes in that automatic council or district."
Repairing potholes leaves a safer, smoother surface for the motoring public, but crews have to practice safety when making repairs. Proper work zone signage and cones make a world of difference in safety when a motorists approach a pothole patching operation. But workers can be at risk from more than just traffic. Hot asphalt loaded into the back of the truck can come tumbling down when a worker scoops out a shovelfull. As Donny Murillo, a driver for King County, Washington State, points out, using a box or unit to contain the hot mix is a safe practice. He operates a Patch King unit equipped with an augering system for deploying mix. "It's V-shaped in design, and it just augers the mix out the back onto a chute," says Murillo. "It's a really safe machine."
Gaillard explains that in the City of Savage, workers manufactured their own kind of shoveling tray off the back end of their unit. "It came with a chute," says Gaillard. "We built ourselves a little material shoveling tray off the back where the guys can just place the material in the hole more accurately and in the proper quantity."
Gaillard explains that the chute functions as more than just a safety measure for his crews. "We use the chute if we're going to do some asphalt curbing," he says. "Then the material will just roll down and make a nice little windrow of asphalt that we can dress off and have our curb." Keeping things moving quickly and safely is a priority for these cities. With the old method of pothole patching losing popularity, the use of new heat-retaining, safe equipment is catching on.
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PHCo and Leeboy - An Electrifying Partnership
If efficiency is what you're after when it comes to spraying asphalt material, has the truck for you. It's Maximizer series provides a completely automatic operation putting the driver in control right from the comfort of his cab. All it takes is one switch to control the spray or bar circulation.
A third advantage is when you're through for the day, the use of efficient Process Heating Company
heaters, allows you to simply plug it in and you're ready to start the next day with a truck with already heated material. This allows for maximum safety and reliability back at the yard all night long.
These two leaders in the industry have joined forces to provide you with truly an electrifying combination, one that is sure to work for you.
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