ZCL Composites Inc. Guide Specifications –
Vertical, Aboveground Fiberglass Reinforced Plastic (FRP) Chemical Storage Tanks
Short form
This specification covers the design, manufacture and supply of single and double wall, fiberglass reinforced plastic (FRP) tanks
for above ground, vertical installations in corrosive applications, with pressures not exceeding 15 psig external and/or 15 psig
internal above any hydrostatic head.
This specification does not cover the design, manufacture or supply of vessels intended for services involving pressure exceeding
15 psig external and/or 15 psig internal above any hydrostatic head. Piping, valves and any other accessories not critical during
tank construction are not covered in this specification.
Long form
Part I: General
A. Acceptable Manufacturer: ZCL Composites
B. Applicable Codes and Standards: FRP tanks covered under this specification shall be filament wound or contact molded
conforming to the appropriate specifications set forth in this document.
1. ASME – RTP 1 - Reinforced Thermoset Plastic Vessels for use in corrosive or hazardous service environments.
2. ASTM D3299 – Filament Would Glass Fiber Reinforced Thermoset Resin Chemical Resistant Tanks.
3. ASTM D4097 – Contact Molded Glass Fiber Reinforced Thermoset Resin Chemical Resistant Tanks (Formerly
covered under NBS-PS 1569).
4. ASTM D2563 – Standard Practice for Classifying Visual Defects in Glass Reinforced Plastic Laminate Parts –
Minimum of Acceptance Level III.
5. ASTM C581 – Standard Practice for Determining Chemical Resistance of Thermosetting Resins.
6. API 12P (Modified) – Shop Fabricated, Atmospheric, Vertical, Cylindrical Fiberglass Reinforced Plastic (FRP)
Tanks (modified to allow for tanks that exceed 1500 barrels in capacity and fittings that are specified by the owner).
C. Qualifications
1. Manufacturer must be able to document ASME RTP-1 accreditation.
2. Manufacturer must be able to document a minimum 10-year successful FRP tank manufacturing record.
Part II: Materials
A. Resin – The resin used shall be a commercial-grade corrosion resistant thermoset that has either been evaluated in a
laminate by test in accordance with ASTM C581 or that has been determined by previous documented service to be
acceptable for the service conditions. Manufacturer will obtain a letter from the resin supplier documenting the
compatibility of the resin within the specified chemical service shall be submitted prior to the bid process.
The resin shall contain no pigment, dyes, colorants, fillers (sand/silica) or extenders, except as follows:
1. A thixotropic agent that does not interfere with visual inspection of laminate quality, or with the required corrosion
resistance of the laminate, may be added for viscosity control but may not be used in the inner surface layer.
2. Resin pastes used to fill crevices before overlay shall not be subject to the limitations of letter A.
3. Ultraviolet absorbers shall be added to the exterior surface for improved performance and resistance to weather.
B. Reinforcement Materials (Glass)
1. Chopped Strand Mat – Chopped strand mat shall be constructed from chopped commercial-grade E-CR or E-type
glass strands bonded together using a binder. The strands should be treated with a sizing that is chemically
compatible with the resin system used.
2. Continuous Roving – Continuous roving shall be a commercial-grade E-CR or E-Type glass fiber with a sizing that
is chemically compatible with the resin system used.
3. Woven Roving – Woven roving shall be in accordance with ASTM Specification D2150.
4. Surface Mat Veil – The reinforcement used for the inner surface shall be composed of either commercial-grade
chemical resistant glass surface mat, an organic-fiber surface mat or carbon veils as recommended by the resin
manufacturer for the specified chemical service environment.
Part III: Laminate Construction Requirements
A. Structural Tank – The corrosion resistant laminate comprising the structural tank (bottom base, cylindrical shell, top
head) shall consist of a corrosion resistant barrier comprised of an inner surface layer and interior layer as well as a
structural layer. In double-wall applications, the laminate shall also comprise an interstitial space between the
corrosion resistant barrier and the structural outside wall of the vessel, which can be monitored for leaks in the
corrosion barrier of the vessel.
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ZCL Composites Guide Spec. – Vertical, Aboveground Fiberglass Reinforced Plastic (FRP) Chemical Storage Tanks
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5.
Inner Surface Layer – The inner surface layer directly exposed to the chemical service environment
specified, shall be a resin-rich layer 0.010 to 0.020 inches thick, reinforced with suitable chemical-resistant
glass fiber surface mat, organic fiber surface mat or carbon veil in accordance with B4 in Part II: Materials
listed above.
Interior Layer – The inner surface layer exposed to the corrosive environment shall be followed with a
layer composed of resin and reinforced only with non-continuous glass fiber-strands applied in a minimum
total of 3 oz/ft2. The combined thickness of the inner surface and interior layer shall not be less than 0.10
inches.
i. Glass content of the inner surface layer and the interior layer combined shall be 27%, or +/-5% by
weight.
ii. The degree of cure of laminate shall be such as to exhibit Barcol hardness on the inner surface
(corrosion barrier) of at least 90% of the resin manufacturer’s minimum specified hardness for the
cured laminate. NOTE: use of synthetic veils will reduce Barcol hardness readings.
Structural Layer – The interior layer, and interstitial space in double-wall applications, shall be followed by
the structural layer which will be either Filament Wound or Contact Molded, depending on the chemical
service environment that is specified:
i. Filament Wound Structural Layer – Subsequent reinforcement shall be continuous-strand roving
in accordance with B4 in Part II: Materials listed above. Glass content of this filament-wound
structural layer shall be 50 to 80% by weight.
ii. Contact Molded Structural Layer – Subsequent reinforcement shall be comprised of 1.5 oz/ft2
chopped strand mat or equivalent weight of chopped roving, or shall be comprised of chopped
strand mat or chopped roving and such additional number of alternating plies of 24 oz/yd2 woven
roving to a thickness as required to meet the physical properties that have been developed in the
design. Each successive ply or pass of reinforcement shall be well-rolled prior to the application of
additional reinforcement. Where woven roving is used, chopped strand glass reinforcement shall
be used between plies of woven roving and for final layers. All woven roving and chopped strand
shall be overlapped.
Top Head – The top head, regardless of shape, shall be able to support a single 250lb load on a 4’ x 4’ area
without damage and with a maximum deflection of ½% of the tank diameter at the area where the load is
applied.
Double-Wall Tanks – The interstitial space between the inner layer and structural wall of the tank shall be
constructed with Parabeam® glass reinforcement material, which provides an integral bond between the
two tank walls, while creating a defined interstice that allows for the free flow of liquid.
i. A monitoring fitting shall be provided to allow for a monitoring sensor to be installed near the
bottom of the interstice.
ii. The interstice of the tank, unless otherwise specified, shall be tested with a 5psi internal pressure
and/or -35 kpa internal vacuum for leak detection purposes.
Part IV: Fittings, Accessories and Options
A. Manways – All closed top tanks shall be provided with a minimum 20-inch diameter roof access manway and cover.
All tanks with a straight shell height greater than 12 feet shall be provided with a flanged side manway with bolted
FRP cover, 1/8” thick gasket suitable for the chemical environment specified and plated bolts.
B. Lifting Lugs – Lifting lugs shall be provided for all tanks over 50lbs in weight. Lifting lugs are to be fiberglass, zinc
plated steel, galvanized or stainless steel.
C. Hold Down Lugs – Hold down lugs shall be provided on all vertical, flat-bottom tanks. The design, number and
attachment of such lugs will be determined by the manufacturer based on wind, seismic and/or any additional loads
that may be specified.
D. Nozzles – Nozzles can be either plate or conically gusseted for additional structural support.
1. Flanges shall conform to ANSI B 16.5; Class 150 drilling pattern
i. Flange back shall be spot faced, smooth and parallel to the front face to produce a true bearing
surface for bolt heads and nuts.
E. Vertical Dish or Cone Bottom Tanks - This type of tank shall include an integral fiberglass skirt for additional
structural support.
F. Threaded Fittings – Fiberglass reinforced threaded fittings shall be installed with laminates inside or outside where
specified.
G. Vents – Unless the specification covers pressure, all tanks covered in this specification must be vented to prevent
damaging the tank. Excess pressure or excess vacuum can be generated during loading and unloading of liquids.
Standard vents include both mushroom and gooseneck styles. The minimum vent size shall exceed the size of the
largest nozzle specified.
H. Ladders and Platforms – If specified, ladders and platforms shall be constructed from fiberglass, aluminum or
carbon steel. All ladders and platforms shall be fitted to the individual tanks in the fabricator’s factory and
disassembled for shipment. Ladders, which exceed 12 feet in height, shall include a safety cage and shall conform to
OSHA and/or PIP standards.
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ZCL Composites Guide Spec. – Vertical, Aboveground Fiberglass Reinforced Plastic (FRP) Chemical Storage Tanks
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J.
Freeze Prevention System – If specified, a freeze prevention system that is suitable for the chemical service
environment specified will be supplied. NOTE: freeze protection options should be discussed with the manufacturer
since there can be extensive additional tooling required to accommodate some systems. Common freeze prevention
systems include, but are not limited to:
1. Urethane spray foam insulation – desired insulation rating and the corresponding thickness of the foam
insulation to be determined by the owner, prior to the bid being submitted, in consultation with the
fabricator. Urethane spray foam insulation shall include an external elastomeric coating that allows
flexibility while providing weathering resistance.
2. Mineral wool insulation – thickness of the mineral wool insulation to be determined by the owner, prior to
the bid being submitted, in consultation with the fabricator. It is common for mineral wool insulation to be
clad in aluminum prior to shipment.
3. Heat tracing – the type of heat trace as well as the frequency to be determined by the owner, prior to the bid
being submitted, in consultation with the fabricator.
4. Immersion heaters – the type of the immersion heater as well as the frequency to be determined by the
owner, prior to the bid being submitted, in consultation with the fabricator.
Tank Base Options – if specified, additional base configurations will be manufactured to suit the application.
Common base configurations beyond typical flat bottom tanks include, but not limited to:
1. Conical base tanks – conical base tanks which allow for full drainage at a variety of different angles.
2. Tank with legs – FRP legs that are structurally bonded to the vessel allow the tank to be raised.
Part V: Identification
A. Label permanently laminated to each tank with the following minimum information:
1. Chemical Service and Concentration
2. Specific Gravity
3. Resin
4. Corrosion Barrier
5. Capacity (volume)
6. Dimensions: Diameter ____ x Height _____
7. Operating Pressure
8. Operating Temperature
9. Date of Manufacture
10. Name of Manufacturer
Part VI: Submittals
Tank fabricator shall submit the following for review and approval prior to fabrication of the tanks:
A. Detailed shop drawings of each tank complete with all accessories fabricated by the manufacturer, as specified and
stamped by a Professional Engineer (P.Eng) with demonstrated experience in the design of FRP tanks.
B. Detailed design calculations of each tank conforming to the chemical service environment specified shall be
submitted and stamped by a Professional Engineer (P.Eng) with demonstrated experience in the design of FRP
tanks.
C. User’s Basic Requirements Specification (UBRS) – required by the provisions of ASME RTP-1 and will be
submitted for review once the customer has entered all of the required information.
D. Detailed Hydro-Test Procedure
E. Detailed Barcol Hardness Test Procedure
F. Fabricators QA Manual
G. Fabricator’s Dimension and Distortion Control Procedure
H. Detailed Shipping, Handling and Installation Instructions
I. A letter from the resin supplier documenting the resin compatibility with the chemical service environment
specified.
J. Fabricator’s standard Inspection Test Plan (ITP) for shop fabricated vessels.
Part VII: Non-Destructive Examination
A. Tanks are to be tested for the degree of surface cure using Barcol hardness and acetone sensitivity methods as
indicated in the referenced ASTM specifications.
B. Tanks are to be visually inspected for laminate quality and workmanship. Visual inspection, at a minimum, shall
meet the referenced ASTM specification. If no specification is referenced, the visual inspection shall meet the
acceptance criteria of ASME RTP-1, Level II, including but not limited to:
1. Appearance
2. Defects
3. Cut Edges
4. Construction Joints
C. After the tank has been installed, a hydrostatic test shall be performed by the purchaser.
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ZCL Composites Guide Spec. – Vertical, Aboveground Fiberglass Reinforced Plastic (FRP) Chemical Storage Tanks
Part VIII: Recommended Shipping, Handling, Storage and Installation
A. General – The techniques and procedures used for handling and preparing RTP vessels for shipping should ensure
delivery of damage free products. The flexural, impact and shear properties of RTP laminated structures are
significantly lower than those of metallic structures. Therefore, special consideration must be given to weight,
weight distribution and contact points during handling, shipping and storage of RTP vessels. These instructions are
general information only. Safety and common sense should be considered at all times. If any doubt exists regarding
the handling procedures, ZCL Corrosion should be consulted.
B. Handling – Impact or excessive distortion can cause crazing of the laminate structure. Therefore, special
consideration must be given to the following. It is recommended that RTP vessels be lifted for moving or
repositioning and not be rolled, slid, dropped or thrown. A spreader bar is required for proper lifting. Woven fabric
rigger – slings of 3-inch minimum width and adequate strength should be used in direct contact for lifting RTP
vessels. Where an unusually long or bulky vessel is involved, special handling procedures may be required to avoid
damage. Lifting cables and or straps must not be attached to, or permitted to come in contact with nozzles, flanges,
gussets or accessories other than lifting lugs, unless specifically approved by the Fabricator. When a vessel is being
lifted using a cable, a guideline should be attached to prevent impact damage caused by swing contact with other
objects.
C. Temporary & Long-Term Storage – During storage or repositioning, RTP vessels should be left or placed in the
shipping saddles or padded dunnage resting only on firm level surfaces. Vessels should not be permitted to rest on
stones, tools, chocks or other small hard objects. When stored outdoors, vessels should be adequately tied down to
prevent movement due to wind or water floatation. Closed vessels should not be completely sealed. Depending on
site storage area conditions, the vessel can be covered with a tarp to protect it from dust, dirt and flying debris.
D. Shipping – Secure to the truck with padded shipping saddles and banding straps that are properly fastened to the bed
of the vehicle. Vessels being shipped in a vertical position should be fastened to the bed of the vehicle with padded
banding for safe shipment. Vessels should be secured on the vehicle with 1 ½ inch or more clearance between the
vessel (including external fittings, nozzles or other projections) and the bed of the truck or railcar. Flange faces 36inches and under should be protected by fully covering the flange and the opening with suitable plywood or waterproof hardboard, securely fastened. In sizes larger than 36-inches, only the flange faces need to be covered. Pipeends and nozzles should be protected by plastic caps, plywood, hardwood or water-resistant cardboard covering and
securely fastened. All internals should be adequately secured and/or padded to ensure safe shipment. Accessory
pipe, fittings and miscellaneous small parts should be crated or boxed. (If Required) Additional protection within the
crate or box may be required to assure that pieces are not damaged. Such protection might include cross bracing, end
wrapping, and/or batten padding. Boxes are to be identified as to contents and purchase order number, or as
otherwise required by the user. Crates or boxes exceeding 50lbs gross weight should be mounted on skids or pallets
to permit handling by crane or forklift truck. Crates or boxes should be secured to the vehicle. All crates, boxes,
skids and pallets should be made of quality lumber and selected fasteners (nails, bolts, lag screws, etc.) that will be
sufficient to ensure safe handling and transit.
E. Receiving Inspection – Prior to removal from the truck, trailer, railcar or shipping container, the vessel should be
inspected to determine if damage has been incurred during transit. Where damage is observed, the carrier’s
representative should be notified immediately. The unloading operation should be delayed until the carrier’s
representative has completed his inspection of the damaged vessel; otherwise, a damage claim may not be honored.
The inspections should include a complete inspection for:
1. External surface damage such as cuts, penetrations, de-laminations or fractured areas;
2. Nozzle damage such as broken nozzles or flanges, or gouged flange faces
3. Internal surface damage such as crazing-white areas with star-shaped surface cracks;
4. Vessel damage at contact points of dunnage, cradles, chocks or hold-down bands.
F. Installation of RTP Vessels – During storage or repositioning, RTP vessels should be placed only on firm level
surfaces that are free of stones, tools and other small hard objects, since contact with such objects can cause
localized damage. The support base surface should be nonporous and free of cracks, depressions and vertical
projections. Reinforced concrete, trowel finished to American Concrete Institute Specifications (ACI-301-72,
Section 11.7.3, “Trowel Finish”) is often used as a support base. The support base should be flat to within ¼ inch of
a horizontal plane. Local irregularities should not exceed ¼ inch. Sloping bases shall be equally flat. All flat-bottom
vessels should be secured in place by bolting to the support base through hold-down lugs. This precaution will
minimize the change of vessel damage at nozzle locations and areas of other attachment due to movement of the
unit. All piping, valves and other attachments must be independently supported. Flanged connections should be
made in accordance with ZCL Corrosion’s recommendations. Where ZCL Corrosion’s recommendations are not
available and where a flanged pipe or fitting is attached to a vessel nozzle with a full-face flange, full-face gaskets
are to be used. If the mating flange has a raised face, it should be machined flat or a filler ring of the proper
thickness should be applied to provide a full flat surface for contact. Gasket material with hardness exceeding 65
durometer (Shore A) should not be used. Metal washers should be used under all bolt heads and nuts that would
otherwise be in contact with the RTP flanges. All flanges should be back spot faced. Nut and bolt threads should be
lubricated before tightening. Bolting take-up torque should be applied uniformly and in accordance with sequence
shown on the drawing. Since the working pressure of a vessel does not exceed 15psig, limit bolt-tightening torque to
the values shown on the drawing.
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ZCL Composites Guide Spec. – Vertical, Aboveground Fiberglass Reinforced Plastic (FRP) Chemical Storage Tanks
G. General Service Requirements – Provisions should be made to prevent vessel contents from freezing. Positive
venting arrangements should be provided. A backup safety system, such as a conservation vent, is recommended.
Provisions should be made to protect the vessel from external damage such as vibration and impact the
manufacturer's limited warranty in effect at the time of purchase.
Part IX: Warranty
Fibreglass Reinforced Plastic - Corrosion Tanks and Pipe
Warranty: ZCL CORROSION agrees that the materials and workmanship to be furnished in accordance with the
specifications contained in the foregoing proposal. Materials and workmanship are guaranteed for a period of one
year from the date of delivery. ZCL CORROSION shall not be held responsible for work done, material furnished,
repairs, erection work or designs made by others unless agreed to in writing by ZCL CORROSION Further it
reserves the right of doing or superintending any necessary repair work. The liability of ZCL CORROSION shall be
limited to the correction, repair, or replacement of defective equipment provided that ZCL CORROSION is notified
of such defects promptly. Any replacement goods provided hereunder shall be warranted against defects in material
or workmanship for the unexpired portion of the one-year period applicable to the goods.
The warranty shall not be applicable if the goods have been subject to any accident, faulty-installation,
misapplication, abuse or misuse; if the buyer has used the goods after discovery of a defect without ZCL Corrosion’s
prior written consent, or if the buyer refuses to permit the seller to examine the goods to ascertain the nature of the
defect.
THIS WARRANTY IS EXPRESSLY IN LIEU OF ANY OTHER EXPRESSED OR IMPLIED WARRANTY
WITH RESPECT TO THE GOODS OR THEIR INSTALLATION, USE, OPERATION, REPLACEMENT OR
REPAIR.
ZCL CORROSION SHALL NOT BE LIABLE BY VIRTUE OF THIS WARRANTY OR OTHERWISE FOR
ANY SPECIAL OR CONSEQUENTIAL LOSS OR DAMAGE RESULTING FROM THE USE OR LOSS OF
USE OF THE GOODS. ZCL CORROSION MAKES NO WARRANTY WITH RESPECT TO THE
INSTALLATION OF THE GOODS OR RELATED EQUIPMENT BY ANY INDEPENDENT CONTRACTOR.
LIABILITY: ZCL CORROSION shall not be liable for any losses, damages or delays due to transportation
difficulties or for any losses, damages or delays due to fire, labour shortage, strike or other differences with
employees, civil or military authority, insurrection, riot, war, accident, shortage of transportation, fuel, labour or
materials, flood, storm, or any other causes or circumstance, whether like or unlike the foregoing, beyond its
reasonable control. Acceptance of materials on delivery shall constitute a waiver of any claims or damages due to
delay whether or not excused by the foregoing. Further, under no circumstances shall ZCL CORROSION be liable
for any special or consequential damages including but not limited to business or economic losses.
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ZCL Composites Guide Spec. – Vertical, Aboveground Fiberglass Reinforced Plastic (FRP) Chemical Storage Tanks
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ZCL Composites Guide Spec. – Vertical, Aboveground Fiberglass Reinforced Plastic (FRP) Chemical Storage Tanks
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ZCL Composites Guide Spec. – Vertical, Aboveground Fiberglass Reinforced Plastic (FRP) Chemical Storage Tanks
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ZCL Composites Guide Spec. – Vertical, Aboveground Fiberglass Reinforced Plastic (FRP) Chemical Storage Tanks