• Components such as manway flanges and top and bottom covers that use composite materials offer advantages on corrosion, chemical and atmospheric resistance.
Topp Industries Inc. is a leading manufacturer of lift stations and components used to move wastewater from homes, commercial buildings and other inhabited structures to treatment facilities.
Steel, Concrete Limits
Many companies in the wastewater treatment industry make their products out of steel and concrete. But steel is highly susceptible to corrosion caused by various chemicals in the wastewater stream. This tendency for corrosion is often accelerated by chloride-rich environments, such as areas with natural salt water concentrations – ultimately shortening the life spans of these lift stations Concrete stations tend to crack as they settle, resulting in leakage and typically higher maintenance costs. Both steel and concrete stations also are extremely heavy, making them difficult to transport and install.
As for stations composed of both steel and concrete, the concrete will inevitably crack over time, allowing chlorides to reach and corrode the steel. When steel corrodes it expands, causing it to lose its bond to the adjacent concrete, often limiting the total life cycle of the list station or worse, resulting in failure of the structure.
These problems can be solved by using composite materials consisting of fiberglass reinforcement in a polymer resin. But open spray-up and many of the older fiberglass manufacturing technologies are slow and labor-intensive.
Composite Options
Topp Industries, of Rochester, IN, avoids these problems, in part, by making lift station components such as manway flanges and top and bottom cover plates out of thermoset bulk molding compound (BMC) and sheet molding compound (SMC). BMC and SMC provide excellent corrosion, chemical, and atmospheric resistance, helping Topp’s lift stations last far longer than similar steel units. In addition, BMC and SMC lift station components don’t crack in the field like those made of concrete. In most cases, thermoset components are significantly lighter than concrete and steel parts of equal strength. Also, the closed molding process used to make thermoset parts is much more environmentally friendly than open composite-manufacturing processes.
