Concrete grinder
A concrete grinder can come in many configurations, the most common being a hand-held Angle grinder, but it may be a specialized tool for countertops or worktops. There are also purpose-built floor grinders that are used for grinding and polishing marble, granite and concrete. Machines that grind concrete floors are usually made to handle much more stress and will have more power to drive the unit as concrete has a much higher sliding friction than marble or granite which is also worked wet, therefore with less friction. In fact some types of marble will spark when it is ground dry, causing deep damage to the marble surface.
All concrete grinders use some sort of abrasive to grind or polish such as diamond tools or Silicon carbide. The diamond tools used for grinding are usually diamond grinding cup wheels, and for polishing are usually diamond polishing pads.
Concrete is usually ground dry for convenience, because it can be done with fewer people than wet grinding although a HEPA filter-equipped vacuum is needed to capture the fine dust produced. Of course concrete can also be ground wet in which case no vacuum is used. Fine concrete dust contains silica which is very harmful to the lungs and can lead to silicosis so all effort should be made to avoid breathing concrete dust. For green building methods many[who?] have seen the benefit of using concrete grinders that are designed for wet grinding. These machines do not require electricity and are run on alternative fuels.
The picture on the right is an example of a concrete floor grinder. This is a Klindex three-head planetary grinder, which has a three-phase motor and will run on single or three phase power.
