President Bill Gorsline was asked by Powder Bulk Engineering to provide insights on what the best mechanical conveyor for fragile materials is for their Supplier’s Tips feature in the July issue of their magazine. Below is an unedited version of what appeared in the magazine.
Whenever a customer describes their product as “fragile” we will first establish exactly what they mean by “fragile”. We find the best way to do this is by understanding the nature of the damage that the material may be susceptible to. Although simple breakage of the material is common, surface damage such as scoring and degradation, causing dusting in dry particles, are also frequent concerns. Once we establish what the customer is needing to avoid we can pretty quickly make an equipment choice and recommendation. Here’s how we do it.
For practical purposes, there are two causes of damage to materials while being conveyed.
1. The free fall of product or more specifically the sudden stop when it hits something solid, this is usually found:
2. The occurrence of relative motion between particles and/or between the particles and a stationary conveyor component as a part of the conveying process i.e. while in the conveyor. Three examples of this would be
Conveyor types that are going to provide the gentlest possible horizontal and incline conveying for fragile materials are:
1. Belt conveyors including flat belt conveyors, troughed belt conveyors, corrugated wall belt conveyors, cleated belt conveyors (inclined), here’s why:
2.Long amplitude and low frequency “vibratory” conveyors where the product is gently move forward by the conveyor and then the tray is quickly brought back to the starting position without bringing the product back with it and without damaging the material as well. Limited to horizontal conveying only.
3. “Z” type bucket conveyors including “C” configuration conveyors, interlocking bucket and pivoted bucket designs, where the conveyor is capable of carrying materials both horizontally and vertically without transfer. (some conveyors are capable of travelling in three planes without transfer). For horizontal and incline use, only the horizontal sections are used.
For all the reasons given previously, when it comes to vertical conveying, the “Z” type of bucket conveyor will be the best choice to handle fragile products whether in a “C” configuration, whether using an interlocking bucket design or a pivoted bucket, the product can be elevated without damage, degradation or spillage. For more information on how we can handle your fragile materials, please contact our application specialists.