The Rotating Grate is composed of cast surface elements mounted on transverse support bars. These are connected to translation chains, which are driven by an electric motor with speed controlled by frequency inverters.

The cast surface elements are provided with small holes of specific diameter to: ensure the proper distribution of air across the entire grate surface and prevent obstruction by ash.

The rotary grate design developed by HPB features an integral tubular shaft, with its ends supported on bearings located outside the furnace.

This arrangement ensures low maintenance, enabling continuous year-round operation. In the event of unscheduled intervention, actions can be carried out without the need to shut down boiler operation.

Cleaning of the Rotary Grate is performed automatically by controlling the translation speed, with adjustments allowing the proper time for complete fuel combustion.

The drive system consists of an electric motor with speed controlled by a frequency inverter and a speed reducer, both installed outside the furnace, allowing maintenance even while the boiler is in operation.

Combustion air is divided into two main parts: part of the primary air is directed to the Rotary Grate and the other part to the secondary air sections, installed on the furnace walls.