Open Top Tanks

Open Top Tanks


Saint-Gobain Performance Plastics high-performance tanks are the best and toughest in the industry. Exacting CAD-based designs, the highest quality virgin resins and tough construction provide excellent solutions for general purpose applications. The tanks are translucent and feature molded-in graduations.

Each tank comes with a matching cover the same thickness as the wall. The open-top unit covers fit like a shoe box; bolted or welded covers are available upon request.

Closed-dome tanks are available for applications requiring a completely closed vessel. The 6" threaded polypropylene covers prevent evaporation and spills. Our open-top tanks are rated for use with 1.8 specific gravity media. If a fiberglass casing is used, the rating goes up to 2.2. Casings provide structural support and prevent bulging at the bottom of the tank. They should be used with rectangular units with any dimension greater than 18 inches. Casings are also required for use with media having a specific gravity greater than 1.8 or for use at prolonged elevated temperatures.

Our stands, mixers, and casings have been pre-engineered for compatibility. Simply choose your tank size and the size codes of the accessories will match.

Fabrication is available for all Saint-Gobain Performance Plastics tanks. Modifications can be made to the covers or the sides. Welded and mechanical fittings can be installed, as well as a full line of accessories. Contact Us for quotations.

Guidelines for Open Top Tank Installations

Materials Overview

High Density Polyethylene (HDPE)
  • FDA 21 CFR 177.1520
  • Hard, Smooth Finish
  • Very Good Chemical Resistance
  • Good Stress-Crack Resistance
  • Max Service Temp-140°F
  • Translucent White
Polypropylene (PP)
  • FDA 21 CFR 177.1520
  • USP Class VI, Non-Cytotoxic
  • Hard, Smooth Finish
  • Very Good Chemical Resistance
  • Excellent Stress-Crack Resistance
  • Max Service Temp-220°F
  • White
Cross-Linked Polyethylene (XLPE)
  • Not FDA
  • Cannot be welded
  • Better Chemical Resistance to HDPE
  • Excellent Stress-Crack Resistance
  • Max Service Temp-140°F
  • Yellow (Bulk Tanks-Gray)
Polyvinylidene Fluoride (PVDF)
  • FDA 21 CFR 177.2510
  • High-Purity Material/Low Extractables
  • Larger sizes require casings
  • Inherent UV Resistance
  • Excellent Chemical Resistance
  • Max Service Temp-230°F
  • Off-White


Maximum service temperature listings refer to temperatures that should not be exceeded for the materials utilized in the specific product line. Many factors including media, specific gravity of media, external stresses, product geometry, environment, and others affect suitability of material.

Structural Designs

Cylindrical tanks feature a stepped-flange design that adds rigidity and strength while helping to contain drips. Tanks over 30 gallons feature a slightly raised bottom that channels liquids to tank walls and fittings. Spoke bottoms reinforce larger tanks over 55 gallons and provide near-total drainage.


Flat-Bottom Cylindrical Tanks

  • All tanks come with covers.
  • Brim capacity 10% over.

WARNING: Never use FRP casings alone as a tank. Always use a liner. For continuous service at elevated temperatures or storage of high specific-gravity materials, always use an FRP casing with your tank.

Flat-Bottom Cylindrical Tanks Chart

Conical Bottom Tanks

  • 30° cone angle (18° for 400 gallons, 45° for 500 gallons)
  • Complete drainage
  • Better dispersal of solids
  • Easy installation of welded or bulkhead fittings
  • HDPE and polypropylene resins comply with 21 CFR Reg. 177.1520 PVDF 21 CFR 177.2510
  • Require metal stands
  • Clearance from the floor to bottom of the tank is 18 inches (12 inches on 10-gallon tank)

Rectangular Tanks

Tank Flange Styles Available
  • Stepped-Flange
  • Easy mounting of small accessories
  • Better drip containment of parts that are dipped
Stepped-Flange With 1/2" Flat
  • To secure equipment support covers
  • Stock tank comes with standard dust cover only; cover, bolts and gasket custom quote
  • Often used in plating operations
  • When ordered with FRP support casings, each tank can support up to 300 lbs. (i.e., plating rods)



Cylindrical Tanks

Tapered General Purpose Container-HDPE
  • Straight, no-lip flange
  • Often used in water treatment
  • Rigid and lightweight
  • Fits through standard door for portability
Closed-Dome Tanks
  • 6" threaded screw closure with silicone gasket
  • 2-inch top bung with buttress thread on HDPE, 2-inch NPS on PP
  • Protects contents from contamination and spillage
  • Reduces evaporation
  • Two mounting flats
  • Domed bottom offers good drainage
  • Graduations in gallons and liters
Accessories and Options
  • Viton closure gasket #620409-0005
  • EPDM gasket 311-1509
  • Metal stand elevates tanks 22 inches from floor-Cat. No. 19009
  • Many fittings available



Cylindrical Tank Stands

Cone tip 18 inches from the floor - Stand should be bolted to the floor - Available with or without mixer supports

Cylindrical Tank Stands Tank Stands

    Sturdy, all-metal stands are available for most Saint-Gobain Performance Plastics cylindrical tanks.

    These stands feature:

    • Welded carbon steel construction
    • Chemical-resistant PUR Paint
    • Fit tanks with or without FRP casing
Floor Stands

Used with flat-bottom tanks.

  • Elevate the mixer to correct height
  • Stand partially encircles the tank
  • Should be bolted to the floor for stability
Elevated Stands for Flat-Bottom Tanks
  • Lift flat-bottom tanks 22 inches
  • 8-inch center hole for drain
  • 5.5-inch rim cut-out for low side fittings
  • Stand should be bolted to the floor
  • Available with or without mixer supports
Elevated Stands for Conical-Bottom Tanks
  • Conform to the tank's cone angle
  • Open at tip to accommodate fittings
  • Conical-bottom stands center drain openings:
    • 30 gallon-5 inch
    • 55, 100, 150 & 250 gallon-7 inch
    • 400 and 500 gallon: 8 inch



Open-Top Tank Mixers
Saint-Gobain Performance Plastics Tanks and LIGHTNIN Mixers

Our pre-engineered packages are available for general mixing/medium agitation of up to 1000 gallons.

Saint-Gobain Performance Plastics tank and mixer packages are designed for liquids and liquid slurries only. We do not warrant these packages for any specific application; only general purpose mixing to these maximum limits:

  • Solids-20% by weight
  • Specific Gravity (batch)-1.2
  • Viscosity-500 centipoise
LIGHTNIN Mixer Features
  • Self-aligning, floating gears optimize load sharing and reduce wear
  • Switch cord and plug are standard on single-phase units
  • Oversized bearings for superior shaft support
  • 115-volt, single-phase motors
  • Standard 1-year warranty
  • Permanently sealed lubrication
  • Motors-Precision-matched to LIGHTNIN mixers. Direct drive or gear drive, depending on tank size. Chemical-resistant housings, 1/4-1/2 hp.
  • Pre-engineered to applicable Saint-Gobain tanks and stands.
  • Totally enclosed.
  • Mounts-LIGHTNIN mixers clamp securely to steel support stands.
  • Mixer Supports- Welded steel with chemical-resistant polyurethane paint. Pre-sized for proper mixer elevation. Integral part of stand for security and rigidity.
  • Impellers-Cast 316 stainless steel impellers are supplied on all mixers.
  • Mixer packages are supplied with one impeller.
  • Shafts-All shafts are concentric, centerless ground, stainless steel.
Available Options
  • Explosion-proof motors
  • LIGHTNIN mixers can be supplied with air motors for use in flammable or explosion-proof environment.
  • Air motors operate using compressed air and require no electricity.
  • These mixers provide an inherent variable-speed feature by merely adjusting your air-control valve and cannot overload.
  • Tachometers for mixers larger than 55 gallons
  • Special PVDF and PTFE shafts and impeller coatings

WARNING: Never clamp a mixer directly to a plastic tank. Always attach the mixer to a separate metal support. Directly attaching a mixer to a plastic tank will void all product warranties. Never position impeller closer than 3 inches from tank wall.



Open-Top Tank Fittings/Accessories

Floating Covers

Maintain continuous contact as liquid level changes; reduce evaporation, fumes and surface oxidation. Very good chemical resistance. Fit only Saint-Gobain Performance Plastics straight-wall cylindrical tanks (Series 11000, 18000, 19000 and 54000). Resin complies with 21 CFR Reg. 177.1520.

Installed Hinges for Saint-Gobain Performance Plastics High-Performance Cylindrical Tank Covers

Flexible PP hinge provides access to cylindrical tanks without completely removing cover. The cover is cut to your specifications. The hinge is installed with stainless steel rivets. Hinge length and exact location must be listed separately on your purchase order. Stainless steel hinges available upon request.