Are you running out of steam?
“Pounds per square inch gauge
(PSIG).” This phrase is one of the most neglected
engineering terms in your plant.
Pounds per square inch gauge is the
measurement of energy required to drive almost every piece of
your equipment, heat your water, furnish steam to your pressing
machines, dry your garments, control washer fill time and
advise you of excessive pressures in your pressure vessels
(tanks, boilers, stills, etc.).
A simple pressure gauge installed at, or
near, equipment, lines, boilers, water heaters, etc., will give
you valuable information to maintain production, increase
equipment life and promote safety.
Where to begin
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If your boiler is rated for 150 psi
operation, then you could safely raise the cut-out and cut-in
pressures 10 psi each.
Smaller horsepower boilers use burners
with cut-out and cut-in modes, but larger horsepower boilers
(60 HP+) work more efficiently with modulating burners which
maintain steam and heat more evenly with more rapid recovery
than off-on burners.
Why the differential of only five psig?
The close differential will keep the
residual heat in the boiler much longer than with a 10 psig
differential, and the desired operating steam pressure is
easier to maintain without much loss during the cut-out period.
Fuel cost is about the same for both cycles.
Looking at the plant with both laundry and
drycleaning/tailoring, the maximum steam pressure goes to the
laundry department, and the reduced steam pressure goes to the
drycleaning/tailoring department.
The maximum steam pressure of 120 psig
will ensure maximum heat to the press heads for good production
and quality finishing, and the reduced pressure of 70 psig will
ensure enough moisture in the steam to remove wrinkles, relax
fibers, protect heat-sensitive fibers, remove water-soluble
spots in the spotting area and give proper heating temperatures
in the drycleaning department. The higher the steam pressure,
the drier and hotter the steam temperature.
The steam pressure is reduced through a
steam pressure regulator (reducing valve) with a pressure gauge
installed on both the inlet and outlet sides to give instant
information that the valve is working properly.
Also, a steam trap should be installed
after the pressure regulator, and the pressure gauge can
indicate the reduced pressure. This arrangement will reduce any
flash steam and rapping caused by the sudden drop in steam
pressure.
For the water heat
The steam-heated water heater, or heat
booster, must have a steam pressure gauge installed at the
steam inlet in order to monitor the proper psig. The proper
steam pressure is between 20 psig and 35 psig on both heat
exchangers and direct steam boosters (water is pre-heated by
return condensate).
The piston-type air compressor produces
best at 115 psig cut-out and 105 psig cut-in. For compressors
over three horsepower, a constant speed unloader-type is more
efficient in energy savings and air pressure maintenance.
In addition to a pressure gauge installed
just after the pressure regulator (reducing valve), which is
installed just after the compressor outlet, another gauge
should be installed after the air drier and after-cooler to
indicate any drop in air pressure caused by any one of these
devices.
Depending upon the distance from the air
compressor to the operating equipment, the air pressure
regulator should be set at 80 psig to 90 psig.
For the laundry and drcyclening departments
Another air pressure gauge should be
installed at the beginning of both the laundry department and
the drycleaning department to indicate any drop in pressure
along the way from the air compressor. Small air gauges should
be installed wherever individual air pressure regulators have
been fitted.
In the laundry department, air pressure
gauges are most important to ensure proper air pressure to
operate the laundry washers which require at least 75 psig to
function properly.
Water pressure is essential for rapid
filling of large washers, therefore, a pressure gauge should be
installed at the beginning of the hot and cold water lines. The
psig needed for satisfactory water functioning is at least 45
psig with 60+ psig desired.
Laundry dryers, operating at high pressure
steam, need 70 psig to 90 psig for rapid and thorough drying,
and low pressure dryers require only 20 psig to 30 psig steam
for efficient drying. Flat work ironers need at least 90 psig
steam to function. Every dryer and ironer must have a pressure
gauge installed on the inlet steam line.
In the drycleaning department, there
should be gauges to indicate air, steam and water pressure
entering each piece of equipment.
The drycleaning machine needs pressure
gauges on the steam line entering at 35 psig (perc) and 45 psig
to 55 psig (petroleum/hydrocarbon).
An air pressure gauge should be installed
at the cleaning machine’s entrance to ensure a working
pressure of at least 70 psig.
The still needs an operating steam
pressure of 35 psig (perc) and 45 psig (petroleum/hydrocarbon)
in addition to high steam pressure of 70 psig needed for
warm-up and “boil-down.” The pressure gauge is
installed just after the still’s steam pressure regulator
(reducing valve).
For proper drying and solvent recovery,
the steam pressures of 35 psig (perc) will give the required
inlet temperature to the drum of 145° F and the required
outlet temperature to the drum of 120° F for lightweight
garments, and it will give the required inlet temperature to
the drum of 165° F and the required outlet temperature to
the drum of 140° F for medium to heavier weight garments.
For proper drying and solvent recovery,
the steam pressures of 45 psig to 55 psig
(petroleum/hydrocarbon) will give the required inlet and outlet
temperatures of an added 10° F to 15° F to the perc
numbers given above for each weight garments.
For spotting
The spotting board must have steam
pressure no greater than 70 psig since steam pressures higher
than 70 psig are too dry for wetside stain removal. Therefore,
a steam pressure gauge installed at, or near, the spotting
board is essential to monitor the steam pressure required.
Are you located in the cold northern
areas? If so, you may want to consider a steam-heated unit
heater to heat the customer service area. This unit needs a
steam pressure regulator (reducing valve) and a pressure gauge
set at 35 psig along with a thermostatic steam valve set at the
desired store temperature.
This psig of steam is great enough to
produce condensate which can be run into the return header
without any backup as long as you install the check valve at
the entrance to the return header and at a 45 degree angle
toward the boiler room.
In fact, all return lines from individual
pieces of equipment should have their check valves installed at
the return header and at a 45 degree angle toward the boiler
room (flow of condensate away).
There are many more applications of
pressure gauges which are too numerous to discuss in this
article, but the most important rule to remember is:
“Read all your gauges every day.”
Operators of equipment must be trained to
read these gauges and maintain the required pressures and
temperatures. Each work area should have the required pressures
and temperatures posted for easy visual instructions.
Owners, managers and supervisors must
understand the importance of reading gauges, and they must do
just that every day (minimum) and whenever they are in an area
of operations during the work day.
Note: My spotting video, ”The
Caplan Method of Stain Removal,” which includes my
comprehensive text (edited by Hal Horning) and the handy
spotting board reference, is available in English, Korean
(video only) and Spanish from the Golomb Group, c/o Dennis
McCrory, 7664 Plaza Court, Willowbrook, IL 60521, phone (800)
679-5856. This video is actually a “Trainer in a
Box” and is a complete training course for both
experienced and novice spotters. My comprehensive text
reinforces all of the background technical material required to
produce a professional spotter. Each method of spot removal is
thoroughly discussed and demonstrated. Bleaching and use of
digesters are explained in addition to basic textile chemistry.
Also available from the Golomb Group, in
English and Spanish, is my video on step-by-step shirt
finishing which includes my comprehansive text in loose-leaf
form outlining each procedure for single-operator and
two-operator cabinet shirt units. Both units are demonstrated
using a cabinet sleever and single, or triple, heated collar
former. This procedure was developed by me for top quality with
no touchup (regular sizes) together with maximum production
without overexertion by its operators. Avoiding shrinkage,
wilting and dipping of the collar, together with its proper
“breaking and forming” on the heated collar former,
are all demonstrated. Both the collar and front buttonhole
placket, the two thickest parts of the shirt, are totally dried
under the press head with no loss of production.
Attractive detailing and packaging of the
hangered shirt, padding, steam pressure and timing are all
discussed. A unique wash formula to give whiter whites,
brighter colors and complete removal of grease and body oils is
included in the loose-leaf text book.
Note: My spotting video,”The Caplan
Method of Stain Removal,” which includes my comprehensive
text (edited by Hal Horning) and the handy spotting board
reference, is available in English, Korean (video only) and
Spanish from the Golomb Group, c/o Dennis McCrory, 7664 Plaza
Court, Willowbrook, IL 60521, phone (800) 679-5856. This video
is actually a “Trainer in a Box” and is a complete
training course for both experienced and novice spotters. My
comprehensive text reinforces all of the background technical
material required to produce a professional spotter. Each
method of spot removal is thoroughly discussed and
demonstrated. Bleaching and use of digesters are explained in
addition to basic textile chemistry.
Also available from the Golomb Group, in
English and Spanish, is my video on step-by-step shirt
finishing which includes my comprehensive text in loose-leaf
form outlining each procedure for single-operator and
two-operator cabinet shirt units. Both units are demonstrated
using a cabinet sleever and single, or triple, heated collar
former. This procedure was developed by me for top quality with
no touchup (regular sizes) together with maximum production
without overexertion by its operators. Avoiding shrinkage,
wilting and dipping of the collar, together with its proper
“breaking and forming” on the heated collar former,
are all demonstrated. Both the collar and front buttonhole
placket, the two thickest parts of the shirt, are totally dried
under the press head with no loss of production.
Attractive detailing and packaging of the
hangered shirt, padding, steam pressure and timing are all
discussed. A unique wash formula to give whiter whites,
brighter colors and complete removal of grease and body oils is
included in the loose-leaf text book.
Stan Caplan has over 35 years experience
in his own high volume dry-cleaning, laundry and tailoring
plant and two package plants with adjoining coin-operated
laundry and dry-cleaning. He is a former chief instructor at
the International Fabricare Institute, The Southwest
Drycleaners Association School, the Illinois State Fabricare
School, the Michigan Institute of Laundering and Dry-cleaning
School, the Mississippi Fabricare Association School and
Louisiana Fabricare Association School, the Pennsylvania
Drycleaners and Launderers Association School (now
Pennsylvania-Delaware Cleaners Association), the Johannesburg
Cleaners Association School (South Africa), the Hyatt-Regency
Southeast Asia School (Singapore and Hong Kong) and numerous
short courses in all areas of the fabric care industry
throughout the US and Canada. Stan offers consulting, training
and engineering services in all areas of the fabric care
industry from customer service area to the boiler room. His
total system (TQM) encompasses maximum efficiency, economy and
product excellent quality. Stan can be reached at 7341 Amberly
Lane, Suite 310, Delray Beach, FL 33446; phone/fax:
(561)496-2548; his e-mail address is:
stancap100@aol.com.
