Conveyor Shaft Materials: Differences between Carbon Steel, Alloy Steel, and Stainless Steel

May 10, 2018

Conveyor shafts are tortured by heavy loading forces. Furthermore, the toughened steel shafts are expected to deal with harsh environmental conditions. Admittedly, the weather isn’t a problem in a packaging warehouse, but what about a mining installation or a quarry? No, there’s no middle ground here, no across-the-board alloy solution. On the contrary, our attention must turn to carbon steel, to stainless steel, and to all other alloy-reinforced steels.

Food-Safe Stainless Steel 

The conveyor equipment under our microscope today is installed in a food processing plant. In here, acidic juices are dripping and watery soft tissues are being processed. Fruit juices or meat pulp, the resulting waste is seeping into the mechanical assembly that drives the conveyor system. Stainless steel pulley shafts are operating behind the scenes. They’re coated in a lustrous chromium oxide finish, a polished coating that’s easy to clean. Best employed in food-safe equipment, stainless steel is easy to wash because of that finish. Bacteria can’t find purchase on the heat-treated metal, nor can any other hygiene-compromising pollutants.

High Carbon Steel: Heavy-Load Conveyor Systems 

We’re leaving the food processing facility behind. In the distance, a mine is at the end of the road. Crushers are pulverizing rocky masses while feed hoppers are delivering the crushed aggregate to vibrating screens. It’s noisy in this mine, and there’s dust flying everywhere. Fortunately, there’s a layer of polyurethane coating the equipment. The engineering rubber cushions hard impacts. Still, it takes the robust outlines of a carbon steel conveyor shaft to properly offset these impacts. The higher the carbon content, the tougher the conveyor backbone becomes. However, these shafts are typically incorporated into a mechanical shell, for a watery element is flowing in the mine. Counterintuitively, it makes more sense to lower the carbon content in a conveyor shaft because high carbon steels are brittle. If the shaft is to operate in a high impact machine deck, a degree of elasticity is preferable. 

There’s a balancing act going on in all of these applications. The addition of waterproof seals offset the aggressive nature of this tug-of-war, but it’s still down to the material engineers to select a steel alloy that will cope with a specific set of conditions. Stainless steel shafts add chromium oxide and other exotic metals to the mix, all the better to balance mechanical toughness against that corrosion resistance feature. As for carbon steels, this group of alloys is gifted with high tensile strength, but it requires a mechanical barrier, some sealing mechanism to stave off water penetration.

Optimized by

Get in Touch

Reach Us