Brushes
Brushes used for manual or mechanical
cleaning should fit the contour of the surface
being cleaned. Those equipped with spray
heads between the bristles are satisfactory for
cleaning screens and other surfaces in small
operations where a combination of water
spray and brushing is necessary. Bristles
should be as harsh as possible without creat-
ing surface damage. Rotary hydraulic and
power-driven brushes for cleaning pipes aid in
cleaning lines that transport liquids and heat
exchanger tubes.
Brushes are manufactured from a variety
of materials—horse-hair, hog bristles, fiber,
and nylon—but are usually nylon. Bassine, a
coarse-textured fiber, is suitable for heavy-
duty scrubbing. Palmetto fiber brushes are
less coarse and are effective for scrubbing
with medium soil, such as metal equipment
and walls. Tampico brushes are fine fibered
and well adapted for cleaning light soil that
requires only gentle brushing pressure. All
nylon brushes have strong and flexible fibers
that are uniform in diameter, durable, and do
not absorb water. Most power-driven
brushes are equipped with nylon bristles.
Brushes made of absorbent materials should
not be used.
Scrapers, Sponges, and Squeegees
Sometimes scrapers are needed to remove
tenacious deposits, especially in small opera-
tions. Sponges and squeegees are most effec-
tively used for cleaning product storage
tanks when the operation has insufficient
volume to justify mechanized cleaning.
High-Pressure Water Pumps
High-pressure water pumps may be por-
table or stationary, depending on the volume
and needs of the individual plant. Portable
units are usually smaller than centralized
installations. The capacity of portable units is
from 40 to 75 L/minute, with operating pres-
sures of up to 41.5 kg/cm^2. Portable units may
include solution tanks for mixing of cleaning
compounds and sanitizers. Stationary units
have capacities ranging from 55 to 475 L/min.
Piston-type pumps deliver up to 300 L/min,
and multistage turbines have capacities of up
to 475 L/min, with operating pressures of
up to 61.5 kg/cm^2. The capacity and pressure
of these units vary from one manufacturer to
another.
In a centralized unit, the high-pressure
water is piped throughout the plant, and
outlets are placed for convenient access to
areas to be cleaned. The pipes, fittings, and
hoses must be capable of withstanding the
water pressure, and all of the equipment
should be made of corrosion-resistant mate-
rials. The choice of a stationary or portable
unit depends on the desired volume of high-
pressure water and the ease with which a
portable unit can be moved close to areas
being cleaned. Other uses of high-pressure
water in the plant can also determine
whether a stationary unit is warranted.
High-pressure, high-volume water pumps
have been used primarily when supplemen-
tary hot, high-pressure water is desired.
Because this equipment uses a large volume
of water and cleaning compounds, it is fre-
quently considered inefficient. This concept
has been applied to portable and central-
ized high-pressure, low-volume equipment
that blends cleaning compounds for dis-
pensing in areas to be cleaned. With a
lower volume and water temperature, it is a
more efficient approach that can effectively
clean areas that are difficult to reach and
penetrate.Low-Pressure, High-Temperature
Spray Units
This equipment may be portable or sta-
tionary. The portable units generally consist
of a lightweight hose, adjustable nozzles,