Maintaining Your Horizontal Liquid Storage Tank

Frequency: Conduct regular visual inspections, ideally monthly, and more thorough inspections annually.

What to look for:
Venting: Verify that vents are clear and functioning correctly to prevent pressure buildup or vacuum.
External: Check for bulges, cracks, discoloration, leaks or any signs of physical damage to the tank body. Pay close attention to areas around fittings and nozzles.
Support Structure: Ensure the tank is properly supported and that the supports are in good condition. Poly tanks require continuous support to prevent stress cracking.
Fittings and Connections: Inspect all fittings, connections, and gaskets for leaks or damage.

Frequency: Clean the tank as needed, depending on the stored liquid and environmental conditions. This is typically done annually, and always prior to switching to a different liquid.

Procedure:

1. Empty the tank completely.
2. Ventilate the tank to remove any residual vapors.
3. Use appropriate cleaning methods:
   • For general cleaning: Use a mild detergent and warm water solution.
   • For stubborn stains or residues: Consult the tank manufacturer or a cleaning agent supplier for recommendations on compatible cleaning agents.
4. Avoid harsh chemicals or abrasive cleaners that could damage the polyethylene material.
5. Rinse thoroughly to remove any cleaning agent residue.

UV Protection: Our tanks are manufactured with UV stabilizers and have a UV rating of 15 on most product materials. This means that after 15,000 hours of exposure to the sun, there will be 50% of UV protection remaining.

Temperature Considerations: Our tanks handle sustained temperatures of up to 120° F (49° C) and intermittent temperatures of up to 140° F (60° C). Freezing temperatures will not have an effect on a polyethylene tank, however they may expand slightly in the cold. 

Chemical Compatibility: Ensure the stored liquid is compatible with the polyethylene material. You can find the Den Hartog Chemical Resistance chart here.

Proper Support: Ensure the tank is installed on a flat, level surface with continuous support across the entire bottom. This is crucial to prevent stress cracking. Common examples would be the flatbed of a truck or trailer for mobile applications. 

Avoid Point Loads: Avoid placing the tank on uneven surfaces or supports that could create point loads and stress concentrations.