Stamped steel trench drain grates are exactly what they sound like. A sheet of metal is mechanically formed into a grate pattern. The trench drain grate is formed from a single sheet without welding. This process typically uses a coil of metal that is fed under a press. The press is fitted with a tool that molds a particular trench drain grate style. The process of the press hitting the metal is called stamping. Stamped trench drain grates are typically supplied in galvanized steel or stainless steel. They can be made in other materials upon request such as brass, bronze, aluminum, etc.
This style of trench drain grating is typically more economical than other types. The down side is that the load rating and durability is typically less than other grate styles. To make Dura Trench stamped grates the best on the market we have made our grates from 12 gauge metal (0.105″ thk). Most of the competing stamped trench grates on the market are either 14 gauge metal (0.075″ thk) or 18 gauge metal (.060″ thk). The Dura Trench grates are 40% to 75% thicker than competing stamped metal trench drain grates. This thickness greatly increases the durability by comparison but they are still relatively weak in comparison to other trench drain grates such as iron trench drain grates or bar grates.
To overcome the lower load class, support bars can be added to the under side of the trench drain grate. While load bars significantly add to the static load capacity we do not recommend this style of grating for hard tire traffic. Through years in the business we have seen these fail even when the load capacity is technically correct. In our expert opinion, these are good choices for foot traffic and low speed pneumatic wheeled traffic.
It is also important to discuss the galvanizing on the steel stamped grates. This trench drain grate is a good choice for a residential driveway or light commercial application. It is not a good choice in areas where fertilizers, pool chemicals, or other corrosive items might be present. The thinner galvanizing on this type of sheet steel is not as effective for corrosion resistance as hot dip galvanizing.
We have made some very nice ornamental pattern trench drain grates from stainless steel, brass, and bronze using the stamping technique. These can be an economical way to get a nice looking quality grate as long as the load rating is DIN class B or lower.