Mahr bar screen protects McCain Foods' pumps in Harbin

In 2007 the managers of McCain Foods factory in Harbin (China) decided modifications were necessary to protect their pump system, and sought a solution from the engineering firm of AMEC Geomatrix, a specialist in the industrial and food processing industry.

AMEC learned that McCain wanted to prevent Quality Control’s large off-cuts (the unusable potato pieces) from entering the pump system, and the engineering firm recommended installing a bar screen to precede the pumps.

Headworks was considered, and won the project based on price, quality of product, and their flexibility. McCain also liked the pivoting design for easy inspection, and the fact that the screen could be supplied optionally with no lower bearings.

A Mahr Bar Screen® with a 1.7 foot screen field and 1” bar spacing was installed into a ten-foot channel preceding the pumps.

Right off the bat, the screen performed beyond expectations. Bill Malyk, principal engineer on the project, received a call from the plant manager reporting that the screen was removing too many French fry pieces and even 1cm cubes of off-cuts from the spuds, which could safely go through the pumps. Thanks to the variable frequency drive on the rotating rakes, and the patented, individually replaceable bars on the screen, onsite modifications made for a simple solution. Every other bar in the screen was removed, then the rotation of the rakes was slowed to allow just the larger unusable potato pieces to be captured and removed via a discharge chute.

After slowing the rakes and removing bars, McCain captured just the intended larger pieces.

“To date, the Mahr Bar is tirelessly removing spuds at the facility and has no issues with operation,” reported Mr. Malyk.