What feeder for easily broken products?

If maintaining the shape and size of the product being fed through your process is important then choosing the right feeder will require careful consideration.

For example, if you have a food product such as a crisp that needs flavouring to be added to it, you don’t want to crush the crisp as it is being fed into the flavouring drum. This is a common problem when handling materials in the food industry that have often been moulded or cooked into a particular shape but can equally apply in other sectors.

So what do we need to consider?

Firstly we need to think about feed rates. For large volumes in the tens of thousands of kilogrammes per hour, your most likely selection will be a gravimetric belt feeder. Belt feeders often work with a simple gravity fed infeed or perhaps another belt conveyor. The raw material lies on the surface of the belt and has little mechanical action applied to it. Your product simply requires enough structural strength to survive the transition on and off the belt. Slow speeds and minimal drops are often enough for this to be achieved and so for high feedrates a weigh belt is a good choice.

For lower feedrates, a loss-in-weight vibratory feeder is most likely to be your best option. A vibratory feeder is either a tube or tray that is moved rapidly back and forth by a vibrating motor mechanism. The product moves along the feeder in a series of “hops” that are generally too fast to be seen but again means that there is very little mechanical action applied to the material being fed and hence it tends to remain intact.

If your product is both fragile and poor flowing then there is a balance to be had between these two properties as some mechanical force may be needed to keep the material moving but if you apply too much, the product may start to break down unacceptably.

In this case the single screw FlexWall feeder may be ideal as this provides a gentle form of agitation to keep the material flowing into the feed trough and an open spiral type screw can push the product forward while causing minimal damage.

With many products in this area having unique properties, equipment testing is a good idea as it may highlight an issue not initially considered. We can arrange these trials for you so please drop us a line and we can start to go through the selection process with you.