Screw Conveyor for Conveying Pork By-Products John Morrell & Company in Sioux Falls, SD

General Description

John Morrell & Company, started curing ham and bacon in England in 1830. Smithfield Foods owns John Morrell & Company along with several other name brands. Smithfield Foods produces over 6 billion pounds of pork per year and is one of the largest suppliers in the world.

The pork processing plant in Sioux Falls, SD had problems with a screw conveyor and needed a replacement. The existing screw conveyor was rusted out and leaking on the production floor. The maintenance manager at John Morrell approached All Power, a local power transmission distributor who turned to KWS to design and manufacture a new and improved screw conveyor for the application.

Design Parameters

1. Product Type – Pork By-Products
2. Material Density – 50 to 55 Lbs. per Cubic Foot
3. Conveyor Capacity – 2,450 Cubic Feet per Hour
4. Moisture Content – 55-Percent Solids
5. Duty – 24 Hours per Day, 7 Days per Week

KWS Advantages

KWS met with All Power and the maintenance manager to discuss the application and determine solutions. After further review, there were several problems that needed to be addressed. The screw conveyor to be replaced was 90-feet long and there were problems with insufficient torque as well as the leakage problems.

KWS upgraded the screw conveyor with heavy-duty construction to eliminate all the problems. Based on the operating conditions observed at the plant, KWS increased the size of the center pipe of the screws as well as the drive shaft diameter to increase the torque rating and prevent future failures. KWS also made the screw conveyor liquid tight to prevent further leakage.

Special Features

The new KWS screw conveyor utilized a flared trough with abrasion resistant steel liners. Flared troughs are designed to handle large pieces of meat by-products without restricting flow rate. KWS also added 3/8-inch thick AR235 liners to provide wear resistance and extend conveyor life. When a liner finally wears out, it can be replaced in the field without removing and replacing an entire trough section.

The new KWS screw conveyor has two sections of removeable perforated trough to allow blood and liquids to drain from the product, reducing the potential for leakage. Since the long screw is supported by the trough liners, double hold-down angles were used to stabilize the screw along the entire length of the conveyor. To increase the capacity of the conveyor, KWS added 12-inch tall channel extensions to the top of the flared troughs.

KWS chose to seal the trough at the drive end with a special seal made from UHMW which rides on the outside diameter of the center pipe of the screw. For ease of maintenance, KWS extended the center pipe through the trough end so the drive shaft to screw connection is outside the trough and removed from the bulk material flow.