At Herberts expensive circulation systems became obsolete when they changed to explosion proof hand pallet truck scales to mix the paint, moving the scale from one component to the other. Thus they work faster, are more flexible in their production planning, and they have lowered their maintenance and investment costs.
"When working with mix coatings, this means that you have to weigh very accurately. With mobile weighing systems, we saved time and money. And we have always been consulting with RAVAS to reach the smallest possible graduation."
- F. JAHNKE, HEAD OF PRODUCTION ENGINEERING
Car repair coatings accurately weighed
Herberts controls world-wide the activities of the Hoechst Group in the area of car, powder and industrial coatings. In Wuppertal 130 tonnes of car repair coatings are produced daily, in 18.000 different colours. These colours are composed of standardised mix coatings, according to a recipe that requires a high accuracy in mixing. For the purpose of manufacture and quality control of this high cost product, weighings are executed at several stages in the process.
Before: high product loss
Before the pipeline system in the warehouse for semi-manufactures ran to a fixed scale, where the recipe for mixing dyes and additives was executed. To avoid differences in concentration within the pipelines, expensive circulation systems were used. When recipes or components were changed, complete pipeline systems - including couplings, pumps and valves - had to be disassembled and cleaned. Occasionally pollution occurred, which spoiled whole product batches. Result: high investment and maintenance costs of the system and a relatively high product loss.
Faster, more flexible and saving money
Now with RAVAS pallet truck scales: a barrel is placed on the weighing hand pallet truck, and driven directly underneath the different dosing stations in the semi-manufactures warehouse, where mixing of the recipe is done. The procedure is faster and more flexible. Since complicated pipeline systems are no longer necessary, considerable savings on investment and maintenance costs are made. The chance of product loss due to pollution has become very small.
From stationary to mobile weighing
In earlier times the end product was poured in 5 litre cans on the automatic packing line. Next to these, 200 litre barrels and containers are filled, for bulk consumption. Since the automatic packing line is not laid out for this, the filling of these barrels and containers is done manually. Both the containers and the product had to be transported to a fixed scale, which resulted in a time consuming procedure. Not anymore with RAVAS pallet scales: the container is placed on the legal for trade weighing hand pallet truck. It is brought to the filling station and the container is filled to the requested weight. In this area as well, work is being done faster and more efficiently. Jahnke:'You can also see the enhanced efficiency when we are measuring residence times. We were only able to take samples during 9 or 18 seconds, which already resulted in 5 litre buckets which our people had to carry around. We don’t have body builders for employees, neither did we want our personnel walking around with one arm longer than the other. Today this is done more economically.'
Before: when dyes are being mixed with liquid binding and solvents, intensive stirring is necessary, in order to avoid lumps and agglomerates. The resulting colour of the coating is strongly dependant on the residence time of the product in the mixer. To check this residence time, a sample was taken regularly, during a certain number of seconds. This sample was brought to a stationary scale, where the weight was extrapolated to a residence time in kg per hour. Since this way of working was very time consuming, only small samples were taken. This influenced the reliability of the measurements in a negative way. With RAVAS: the weighing hand pallet truck is driven straight under the vessel containing mixed and stirred product, a tare is done, the clock is started and after 3 minutes the increase in weight is registered. The residence time of the product in the machine can be determined faster and more reliable. Quality control is more efficient.