Chemical Engineering October 2017 - 74

CPI Product Review 2017 Special Advertising Section
Thermal-Fluid Sampling: Where and How to Sample
Where and how thermal fluid is sampled can make all the difference in what the
test results reveal.
W
here a sample should be taken
is simple - any location where
there is flow and the temperature is
above 180°F. A blowdown valve on
the pump suction strainer housing
is a good bet since that's where the
lowest pressure and temperature
exists in most systems. Piping drain
valves will work as long as several
containers worth of fluid are purged
before taking the sample. Expansion
tank or thermal buffer tank drain
valves are tempting as a sample location
because they are (usually)
cool and (mostly) accessible. Don't
do it. For a long list of reasons, it's
almost the worst place to take a
sample, just above scooping it off
the floor near the pump.
Taking the Hot Oil Sample
How to take a sample is not quite
as simple. Why? Because improper
sampling practices can actually alter
the physical characteristics of the
sample that will be measured.
Ideally, a sample should be
See the one-minute video at www.
paratherm.com/fluid-analysis
Paratherm's new fluid-analysis lab, completed in
2016, continues to add equipment and capabilities
taken directly into a glass sample
jar so any contamination or carbon
in the fluid is easy to measure. The
problem with glass is that it can
shatter if the sample is taken too
hot (above 250°F). So if the next
heater shutdown isn't scheduled
until the Phillies win the pennant,
install 18-24 " of 1/4 " copper tubing
on the sample port and bend a loop
or two through a bucket of water.
This will knock the sample temperature
down the couple-hundred
degrees needed to keep the glass
from breaking. Or take the sample
in a clean metal can with a screw
top and send that in (just remember
to label it with the system name
and date). Do not take the hot
sample in a metal " cooling " bucket
and then transfer it to the sample
container.
www.paratherm.com
Plastic Control Valves Handle Corrosive Chemicals
Collins 2-in. valves and actuators are specially designed to handle corrosive fluids - acids,
bleaches, chlorine, pH control - and aggressive environments
C
ollins Instrument Company's line of
economical 2-in. flanged plastic control
valves handle corrosive liquids including
hydrochloric acid, caustic, sulfuric acid, and
many others. With bodies of either PVDF
or polypropylene, these highly-responsive
control valves are specifically designed for
use with corrosive media and/or corrosive
atmospheres.
Suitable for applications in numerous industries,
including chemical, petrochemical,
pulp and paper, and municipal, these valves
are extremely corrosion-resistant, and feature
fast-acting positioning (stroke rate
approximately 1⁄2 in./s). They are available
with a wide selection of trim sizes, in globe,
angle, and corner configurations.
The differential-area piston eliminates
the necessity for auxiliary loading regulators.
All actuator parts apart from the integral
positioner are molded of glass-filled,
UV-inhibited polypropylene. Before shipment,
the aluminum positioner and a portion
of the cylinder are immersed in Dip
Seal to provide atmospheric protection.
74
environments that can attack the outside
of the valve and actuator. Collins plastic
control valve packages withstand salty marine
atmospheres as well as industrial environments
that are too corrosive for metal
valves and actuators.
Plastic valves and actuators from Collins
The integral positioner eliminates the need
for external linkages which are subject to
corrosion and malfunctioning. Valves may
also be furnished without a positioner for
on/off applications.
Collins also offers a plastic pneumatic
actuator. The combination of a plastic actuator
and a plastic valve body provides an
effective way to handle both corrosive materials
flowing through the valve, and harsh
Collins actuators incorporate a unique
internal locking ring to attach the cylinder
to the yoke. A semicircular groove is machined
inside the lower edge of the cylinder,
and a matching groove cut in the yoke.
When the yoke and cylinder are assembled,
a flexible polypropylene rod is inserted into
the groove through a slot in the side of the
cylinder, securing the two sections together.
Along with its corrosion resistance the
Collins control valve features a stem packing
arrangement that virtually eliminates
the problem of fugitive emissions, thereby
protecting the environment.
Located on the Texas Gulf Coast in
the town of Angleton, Collins Instrument
Company has been serving the chemical
and petrochemical industry for over
65 years.
CHEMICAL ENGINEERING WWW.CHEMENGONLINE.COM
www.collinsinst.com
OCTOBER 2017

http://www.paratherm.com/fluid-analysis http://www.paratherm.com http://www.collinsinst.com http://WWW.CHEMENGONLINE.COM

Chemical Engineering October 2017

Table of Contents for the Digital Edition of Chemical Engineering October 2017