Increase of efficiency and good rate of return with optimising empty drum handling logistics.
It’s the drum that has made its way worldwide in various internationally standardised versions as a container for liquid and paste-like materials. A distribution of liquid and pasty products for industrial employment or application isn’t imaginable any longer without 200 litres drums! They do comply with all requirements for a safe transport and storage either of hazardous goods or foods.
There is a strong logistic challenge to face when filling drums fully automatic, for example with a Feige drum filler. Up to 120 steel bunghole drums per hour each having a volume of 216,5 ltr. are positioned, debunged, filled, rebunged and reliably closed with a seal cap.
As a result thereof, this quantity of drums (120) is demanded as empty drum in-feed and thus multiplies with the number of available automatic drum fillers accordingly!
Where to let this mass of drums?
Imagine, a Jumbo-truck is arriving at filler’s site and is unloaded immediately after. Strong arms lift the empty drums out of their stack and put them onto a telescopic conveyor feeding them onto a roller conveyor. Mostly the empty drums are directly led toward automatic drum fillers. Thus drum-supply and drum-filling are directly linked. Only that sort of drums which is actually unloaded can be filled. Such a direct dependency is absolutely not wanted and they tend to in-termediate storage with sort separation.
For the storage of single drums we have basically two possibilities:
If you dispose of sufficient property, storage roller conveyors take over the drums in same speed as unloading is done and advance them cycle by cycle to those filling machines where provided.
If, however, there is not much space available, an empty drum silo offers the required buffer function with capacities from 900 up to 3000 empty drums. The 200 litre-drums are stacked row by row in the particular cells by the integrated silo stacker. This stacker also does the de-storage (retrieve) row by row and moves the empty drums out towards the filling machines.
How to rationalise manual unloading
The manual handling of empty drums not only requires enormous physical strength – don’t for-get: an empty drum weighs abt. 20 kgs – but also the recovery times of the working personnel have to be considered and the aspect of safety-at-work mustn’t be neglected. To improve work-ing conditions and rationability of work Messrs. Feige has very early developed an automatic sys-tem for unloading of empty drums.
The unloading device drives onto the truck on chain conveyors and moves towards the triple-stacked load. Short before reaching the drum rows to be unloaded it stops. The vacuum grippers move out and press around the drum coats. The unloading device moves back into base posi-tion. Here, one drum row after the other is put onto the roller conveyor and drum by drum is ad-vanced into the drum storehouse.
However, this sort of system turned out to be not very well accepted and practicable as the trucks were of different construction and moreover, the different loading principles and practices
couldn’t be unified.
Why not pallet loading?
Especially for pallet with drums the CP3 and CP9 pallets with the dimensions 1140 by 1140 mm have been developed. Three pallets with each four drums on stacked in 3 layers reached a total height of abt. 3100 mm. These huge stacks could only be handled and transported by low-floor vehicles with “elevating roof” – to be lowered during drive.
Unloading is then done with a fork lifter at the filling place. This avoids a good deal of personnel-intensive hard work.
High efficiency for the transport and the storage of steel drums offers the employment of a multi-cycle plastic pallet system. It consists of a deep-drawn solid 4-way-pallet and two light tray pads. 12 empty drums thus stand on a surface of 1200 x 1200 mm compact in a lot, well protected against dents and paintwork. The minor thickness of the tray pads allows the loading on a cus-tomary truck.
Apart from an increase in quality it is of great advantage that the empty drums are aligned exactly to fit the pallet’s outline. This enables a handling with an automatic device. Drums which are pro-duced in a 4,5 second-cycle in the drum-factory can be employed automatically as 4-drum-lot in the plastic pallet system. The truck driver can safely move and load the twelve-drum-stack with a simple pallet lifter and also unload same at the fill place. The triple-stacks are stored on pallet conveyor tracks. Connection of an automatic warehouse-management is absolutely possible.
An exact positioning on the pallets makes it comfortable to depalletise the drums fully automatic by means of an articulated robot and put them on roller conveyors. These advance the drums to the automatic drum fillers.
Drums which are supposed to be filled in one lot on an automatic pallet filler, can also be placed exactly on CP3 or CP9 pallets, if required.
After de-stacking of each drum-layer the intermediate tray-pads are layed aside in sets. These sets are nestable again so that the transport back to the drum manufacturer is done in a volume-reduced way.
“This system of empty drum logistics has a great future” was the promising comment of a produc-tion manager of a central filling enterprise of a big chemical company. “Even without automatic de-stacking this system offers brilliant storage capacities, because also two triple-stacks can be piled”.
After all, 24 drums are stored safely on a surface area of 1200 by 1200 mm!
