General
- Frequently Asked Questions
1. What
makes poly tanks a good choice for my chemical storage/application?
2. What chemicals can I store in your tanks?
3. What material does Snyder use to manufacture
it's poly tanks?
4. Which tank material is best?
5. How heavy a material can polyethylene tanks
hold?
6. What is the wall thickness of your tanks?
7. Are your tanks FDA compliant?
8. What is the maximum temperature that your
tanks will withstand?
9. Can I store petroleum products in your tanks?
10. Can I store BIODIESEL in your tanks?
11. Can your tanks be pressurized?
12. Can your tanks be buried?
13. What is the warranty on your tanks?
14. How many years will my tank last?
15. Will freezing temperatures hurt my poly
tank?
16. Is there some way to tell when my tank
was made?
1. What
makes poly tanks a good choice for my chemical storage/application?
Poly tanks are lower cost than stainless steel or fiberglass
Lightweight - less than one-half the weight of steel
Seamless construction for easy cleaning and leak proof service
Exceptional Impact resistance
Broad range of chemical resistance
Better weatherability
Available in a variety of resins
Translucent when molded of natural resin for visible liquid level
Virtually maintenance free
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2. What
chemicals can I store in your tanks?
Poly tanks have a broad range of chemical resistance to both Agricultural
and Industrial chemicals. For Industrial Chemicals refer to the
Snyder Chemical Resistance Recommendation Chart on that site or
contact the chemical supplier to see if their product is compatible
with high density linear polyethylene (HDLPE) or cross-linked
polyethylene (XLPE). If they cannot answer your question, call
Snyder Industries and we will be happy to research it for you.
Try to have as much information available as possible such as
the temperature of the product, the percent concentration of product
(Ex: Sodium Hypo chlorite, 15%) etc.
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3. What
material does Snyder use to manufacture it's poly tanks?
Snyder uses HDLPE (high density linear polyethylene) to manufacture
our tank line. High density linear polyethylene has good structural
rigidity and impact resistance. It is resistant to a broad range
of chemicals including sulfuric acid, sodium hypo chlorite, and
sodium hydroxide.
We also offer, for specific applications
XLPE (cross-linked polyethylene). Cross-link polyethylene has
excellent structural rigidity and impact resistance. It is used
as an alternative to HDLPE for storing surfactants or solvent-based
chemicals, or for higher service temperatures.
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4. Which
tank material is best?
General guidelines of material selection are not advisable. It
is always best to provide the tank manufacturer with specific
application details (chemical, concentration, specific gravity,
temperature, dimensions, mechanical loading) so a proper tank
design recommendation can be made by the factory and/or your Snyder
distributor.
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5. How
heavy a material can polyethylene tanks hold?
A tank with a specific gravity of 1.5 can hold a liquid up to
12.5 pounds per gallon at 100 degrees F. A tank with a specific
gravity of 1.9 can hold a liquid up to 15.75 pounds per gallon
at 73 degrees F. Please note that an increase in liquid temperature
will substantially decrease the specific gravity rating. Also,
certain chemicals have environmental stress cracking agents in
them so higher specific gravity tanks are needed to compensate
even though the weight of the chemical may be lower. Please refer
to the Snyder Chemical Resistance Recommendation Chart or call
Snyder Industries to determine which tank design is best suited
for the chemical application.
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6. What
is the wall thickness of your tanks?
Because Snyder tanks have a stratiform wall thickness (varies
from top to bottom on a tank), wall thickness is not the best
gauge for determining the quality of a tank. The very bottom of
the tank is the thinnest part of the tank and is made that way
to flex when the tank is empty or full. The actual weight of the
tank is also not a good comparison when shopping for tanks. Just
because a competitor may use more material in the tank does not
make it a better tank. That is determined by the resin, mold design
and the steps taken during the rotomolding process. Lower grades
of resins will require a thicker tank wall to compensate.
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7. Are
your tanks FDA compliant?
The resin used to manufacture our linear polyethylene tanks (HDLPE)
meet specifications contained in FDA Regulations 21 CFR 177.1520,
© 3.2 an so may be used as an article or component of articles
intended for use in contact with food, subject to any limitations
in the regulation. Cross-linked polyethylene (XLPE) tanks do not
meet FDA regulations. The HDLPE resin that Snyder uses is also
NSF 61 listed.
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8. What
is the maximum temperature that your tanks will withstand?
Linear polyethylene (HDLPE) storage tanks have a maximum storage
temperature of 130 degrees F. Cross-linked polyethylene (XLPE)
storage tanks have a maximum storage temperature of 140 degrees
F.
NOTE: The leading manufacturers in this industry design their
tanks based upon 100 degrees F with ASTM D 1998 calling out 73
degrees F. It is important to contact the factory when your application
will continuously be above 100 degrees (ambient). The tank can
be designed specifically for your elevated temperature application.
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9. Can
I store petroleum products in your tanks?
We do not recommend storing petroleum products in our tanks because
they will permeate (soften) the tank walls. Contact Snyder with
your specific application. You will find that aromatic hydrocarbons
and halogenated hydrocarbons will not be recommended for polyethylene.
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10. Can
I store BIODIESEL in your tanks?
Biodiesel is the name of a clean burning alternative fuel, produced
from domestic, renewable resources. Biodiesel contains no petroleum,
but it can be blended at any level with petroleum diesel fuel
to create a biodiesel blend. Biodiesel or B100 (100%) refers to
the pure fuel. Biodiesel blends or BXX refers to a fuel that is
composed of a % of biodiesel blended into a conventional fuel
(example B20 = 20% Biodiesel blended with 80% conventional fuel).
Snyder has conducted chemical compatibility
testing on B100. Our chemical compatibility testing showed that
Snyder’s uniquely processed HDLPE and XLPE resins are compatible
with B100. From our chemical compatibility testing, Sii recommends
ONLY above ground 1.9 specific gravity Industrial (ASTM) designed
tanks (600 psi hoop stress) for B100 applications. Snyder does
not recommend below ground, agricultural or other non-ASTM designed
tanks to be used in this application.
Snyder’s warranty for biodiesel
B100 applications is one year (1) against defects in material
and workmanship. Snyder may offer additional warranty other than
the one (1) year warranty stated above. In such cases these warranty
statements will be in writing only from Snyder.
Snyder’s chemical compatibility
testing does not include any biodiesel blends so Snyder has no
recommendation for biodiesel blends at this time.
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11. Can
your tanks be pressurized?
No, our tanks cannot be pressurized. They are all designed to
atmospheric pressure.
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12. Can
your tanks be buried?
Tanks specifically designed for above ground use cannot be put
underground because the weight of the ground around the tank can
cause the wall to collapse. If you have an application for a below
ground tank we do have a cistern and septic tank line available
that is designed for below ground use.
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13. What
is the warranty on your tanks?
Snyder warrants to the purchaser for any manufactured tank product
proven to be defective in material or workmanship within 3 years
from date of original invoice from factory. An extended tank warranty
may be available as a purchased option for an additional 2-year
period (total of 5 years) for some chemical applications. Snyder
also offers chemical specific warranties for industrial vertical
& double wall tanks for certain chemical applications including
sulfuric acid, sodium hypochlorite and others. Contact Snyder
on questions regarding warranty for your specific application.
Snyder warrants to the purchaser for
any manufactured Intermediate Bulk Container (IBC) or dry material
handling product proven to be defective in material or workmanship
within 2 years (for polyethylene) and 1 year (for steel) from
date of original invoice from factory. Contact Snyder on questions
regarding warranty for your specific application.
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14. How
many years will my tank last?
There are many variables that can have an effect on the life of
a polyethylene tank.
The type of material being stored in
the tank, it's concentration, and temperature. The temperature
of the application can be a factor, especially if the tank design
is not based upon the temperature of the application. Some applications
may permeate the polyethylene at elevated temperatures. Special
considerations - some chemicals will have long term affects on
the polyethylene and may require special considerations. As an
example, sodium hypo chlorite will degrade from UV exposure and
elevated temperature. As it degrades it can build up sediment
in the bottom of the tank. If this sediment is periodically flushed
from the tank it will extend the life of the tank.
Installation and PIPING! - The number
one reason for tank failures is due to improper installation.
It is important to follow Snyder's "Guidelines for Use &
Installation". Having flexible connections that compensate
for the expansion and contraction of the tank will extend the
life of the tank.
Is the tank used indoors or outdoors?
The amount of U.V. exposure will be based upon the time of exposure
and the closeness of the installation to the sun (elevation).
What part of the country are you in? Tanks used outdoors in states
subjected to more intense sunshine will be more affected by the
sun. UV rays will have a detrimental effect on the life span of
all poly tanks.
Storage or process - Is the tank a
holding tank or a processing tank? A tank that is continuously
cycled will see more stress then a tank that remains at one level
or close to one level for extended periods of time. Tanks with
excessive agitation may also be exposed to undo stress. Stationary
tanks will also not see the stress of a tank that is being transported.
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15. Will
freezing temperatures hurt my poly tank?
Freezing temperatures will not have an affect on a polyethylene
tank, however, if there is liquid in the tank, make sure the freezing
liquid has enough head room to expand.
Snyder utilizes a test called "Low
Temperature Impact Resistance". This is a test utilized by
both the ARM (Association of Rotational Molders) and ASTM D 1998.
Snyder has testing capabilities that exceed the requirements of
ARM and ASTM D 1998. They call out -20 degrees F for the test,
but Snyder has conducted testing at -40 degrees F. This test is
critical to determine if the resin has been properly processed
and it will give you an idea as to the temperatures that the resins
can see. It is important that efforts be made to avoid impacting
the tank, especially with sharp items, at any temperature.
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16. Is
there some way to tell when my tank was made?
Snyder tanks are produced with a molded-in serial number (wheel-date/month
format). In addition, the tank's bar code label has a 10-digit
serial number and date of manufacture. Your Snyder Sales or Customer
Service person, can help you interpret the date of manufacture.
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