Identify the chemicals to be stored in the tanks. Be certain to obtain a Certificate of Composition, MSDS (Material Safety Data Sheet) or other data from the chemical supplier so that the actual chemical compounds can be identified properly to evaluate the effect of the chemical on polyethylene storage containers. Be sure to check that the tank, fittings and fitting gasket material are compatible with the chemicals to be contained and the anticipated storage temperatures. Review the Chemical-Resistance-Data1. This will determine if the chemical to be stored is compatible with polyethylene. If this resistance data does not list the chemical you intend to store in the tank, contact the chemical manufacturer for recommendations regarding storage in polyethylene tanks.
Wall thickness varies from top to the bottom of the tank. Our tanks 2000 gallons or smaller tend to have an even wall thickness due to the roto-molding process. Ace Roto-Mold standard tanks have a specific gravity of 1.7. We use the right amount of material and resin grades in order to insure that specific gravity is reached. We do provide wall thickness maps for our Vertical tanks 5000 gallons and up as well as our Cone Bottom tanks 4600 gallons and up. Please consult the factory regarding these maps.
Depending upon the chemicals to be stored, Ace Roto-Mold tanks will handle sustained temperatures of up to 120° F (49° C) and intermittent temperatures of up to 140° F (60° C). Consult the chemical manufacturer or Chemical-Resistance-Data1 for recommendations regarding storage in polyethylene tanks and service temperature limits. Please note that higher service temperatures will lower the specific gravity rating of your tank.
Ace Roto-Mold tanks are offered in medium and high density polyethylene. The polyethylene utilized in the manufacture of Ace Roto-Mold tanks depends upon the size of the tank. There are minimal differences in the characteristic between medium and high density polyethylene. High density polyethylene offers a slightly higher density, chemical resistance and impact resistance than medium density polyethylene. Vertical Tanks 3100 gallons and larger, Cone Bottom Tanks 4600 gallons and larger, all Septic and Cistern tanks, all Crop Care Tanks as well as the 2350, 2750 and 3250 gallon Free Standing Leg Tanks are all made standard in high density polyethylene. Please note that all Ace Roto-Mold tanks are available in high density polyethylene if requested.
Freezing temperatures will not have an effect on a polyethylene tank, however if you plan to keep a liquid in the tank that you know will freeze, be sure to leave sufficient room for expansion. Be aware there is a greater chance of a polyethylene tank cracking during transportation in cold temperatures.
Fittings that are exposed to chemicals will have a low temperature rating equivalent to the freezing limit of the chemicals the fitting is exposed to. Note that heaters, heat bands or chemical inhibitors that prevent chemical freeze up will allow the fittings to be exposed to ambient temperatures below the freeze point of the chemical. Again, the low temperature rating of all fittings must be above the point at which the chemicals free or solidify.