Increasing the reliability, service life and power savings of geared motors in the meat industry

Major New Zealand meat processor the Alliance Group needed to upgrade its carton conveyors at its Dannevirke, Hawkes Bay, processing plant. In particular, in the boning room it was time to move on from the older powered roller technology to a modular belt design driven by a highly efficient drive package. There were three conveyors to be updated - two straight and one with a large radius.

Another problem the plant was experiencing was overheating in the existing worm geared motors. These motors were too hot to touch even though the ambient temperature inside the boning room was 7°C. The inefficient worm geared motors were failing within a very short service life of up to six months.

Alliance Engineer Dennis Rodgers wanted the new geared motor package to offer increased reliability and an extended service life. The other major criteria were that the new drive package must be suitable for the aggressive washdown environment.

Alliance turned to its power transmission supplier - Russet Engineering Supplies - to recommend and provide the leading-edge technology for the geared motor drive package for its conveyors’ upgrade.

NORD Drivesystems’ NORD 2-stage helical bevel gearbox complete with the new NORD HM series smooth exterior electric motor was recommended.

The three new modular belt conveyors manufactured by the Alliance Group for its Dannevirke processing plant. All components included on these conveyors are selected for their suitability and ultimate reliability for the washdown environment inside the boning room.

The NORD 2-stage helical bevel gearbox incorporates oversized bearings. This technology offers a high overhung output shaft load capacity and the large bearings extend the reliability and ultimate service life of the geared motor. The 2-stage helical gear set is 97% efficient which further enhances the drive package’s efficient capacity to transmit maximum torque with minimum demand to the electric motor power.

The HM series electric motors feature a smooth exterior surface, with no cooling fins at all. All exterior surfaces are sloped to facilitate flow of water and washdown off the surface. The electric motors are MEPS2 compliant (AS/NZS1359.5) and are rated for S1 continuous duty.

The complete NORD geared motor assembly was coated with NORD’s Severe Duty Extreme Stainless Steel coating system (NSD), which is suitable for hygienic and food applications including washdown with aggressive chemicals. The NSD coating sets extremely hard and will not chip or crack, unlike other surface products such as two-pack epoxy paint. The NSD coating has particular resistance to aggressive cleaning chemicals such as sulfuric acid, hydrochloric acid and caustic soda, making it suitable for the meat processing industry. The NSD coating encapsulates the entire geared motor assembly, prohibiting the ingress of water and chemicals under the exterior surface.

The two-year factory warranty also enhanced Alliance’s buying decision as this was new technology and Alliance wanted to minimise any unforeseen risk