What is a Mechanical Bar Screen

Solid Liquid Separator March 28, 2025 Mechanical Bar Screen

A mechanical bar screen is a grid system used for removing debris from wastewater. The screen operates with a mechanical cleaning system and is typically installed at an angle of 60° to 75°. The water passage area of the screen should generally be at least 1.2 times the effective area of the inlet pipeline or channel. There are various types of mechanical bar screens, including chain-type, rotary rake-type, swing-arm-type, and wire-drawn types.

1. Chain-Type Bar Screen Cleaner

Working Principle:
The system operates by driving two rotating chains using a transmission device. Attached to the chains are rakes that lift and remove debris caught on the bars of the screen. As the chains cycle, the rakes collect the debris, lift it to the top, and then scrape the debris off into a discharge hopper using a buffer discharge mechanism.

Application:
This type of screen cleaner is suitable for small to medium-sized wastewater treatment plants with shallow depths.

2. Rotary Rake-Type Bar Screen Cleaner

Key Features:
Unlike traditional bar screens, this type has no screen bars. Instead, it uses numerous small rakes connected to form a large rotating surface.

Working Principle:
The rotating rake surface, driven by a transmission device, cycles continuously. During its rotation, the rakes capture debris, lift it to the top of the screen, and discharge it by following a specific discharge path.

Application:
This type of fine bar screen, with screen gaps ranging from 0.5 to 15 mm, is also suitable for small to medium-sized wastewater treatment plants.