Key Technology

June 2013

Key Technology designs, manufactures and delivers a variety of mechanical sizing and grading equipment. This line of versatile sizers and graders enables food processors to transfer and classify product efficiently—while removing field debris, broken pieces, seeds, juice, fines, and other targeted material. The systems offered by Key include the following:

  • Diameter Sizer: Grades product by diameter and is frequently used in either dry or wet receiving to remove dirt, rocks, and other undesirable material.
  • Length Sizer: Generally used for grading wet, unpeeled potatoes of a target length or smaller.
  • Flite  Roller Table: Removes dirt, rocks, vines, EVM and small or broken pieces, enhancing receiving efficiency with first-pass cleaning and grading.
  • Sliver Sizer Remover & Precision Size Grader: Adjustable precision-machined stainless steel rollers widely used for removing fines, slivers, and targeted small product.
  • Rotary Size Grader: Grades product by length, removing nubbins, short pieces and snipped ends while conveying good product downstream.

Maintenance Tips

Most Key sizers and graders utilize very similar components so maintenance and troubleshooting is basically the same for all systems.

The guidelines provided in your technical manual should be considered the minimum frequencies for required maintenance. Your plant environment, specific product type and condition, maintenance methods and schedule are all factors of a good maintenance program.
Diameter SizerRecommended preventative maintenance:
  1. Bearings on all sizers and graders should be lubricated daily during periods of operation.
  2. The adjustment system should be lubricated biweekly or after wash down.
  3. For chain driven sizers or graders - spray food-grade silicone on the chain monthly and after wash down.
  4. For equipment with a chain oiler -  check the oil reservoir monthly and fill as needed.


Too much good product in the reject stream or build-up of product on the grader

Start by inspecting the grader and the rollers. It could be as simple as product residue build up or some other material blocking the rollers.
Check the adjustment block for alignment. You should be able to fully close the assembly block with both sides closing completely. If you are unable to adjust the assembly, check the spindles for residue build up. Lack of lubrication could cause the worm gear to jam, or the worm gear could be worn and need to be replaced. Finally check for stripping on the adjusting blocks and spindles.

Thank You!

Our global services team is here to assist you with all of your training, service and parts needs.
Contact us at:

Europe, Middle East, India & Africa +31 (0)345 509900

Australia & New Zealand +61 03 8710 8200

North America and other regions +1.877.UPTIME1 (+1.877.878.4631)


Your Service Team
Key Technology, Inc.

Key Technology 150 Avery Street, Walla Walla, WA 99362 USA | +1 509.529.2161 |

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