Example: Fully-automatic glass batching preparation
In one of the most modern glassworks in Europe, near Berlin, about 2 billion bottles and other glass packaging items are produced per annum. The manufacturing process begins in the central glass batching house. Here, up to 2400 t daily of glass finished batches of silica sand, residual glass fragments, soda and other additive materials are processed with the highest level of dosing accuracy and then conveyed to the furnace. The fully-continuous operation of the system 365 days a year places particularly high demands on the reliability and stability of the conveying technology. The high resistance to wear of the conveyors against the abrasive, sharp-edged material conveyed and high temperatures is achieved by a special reinforcement of composite materials. Dust-proof, encased conveyor conduits, with unbalanced vibratory drives, implement the transport between the raw material bunkers. Additional impact vibrators at the bunker walls prevent setting and bridge formations.
The entire system is controlled fully-automatically from a central supervisory facility, using control systems. Thus the glass batching house can be operated completely "unmanned" and a continuous and absolute dosing accuracy is guaranteed - an indispensable necessity for high-value final products. The highest level of dosing accuracy for perfect glass packaging.
| Material conveyed | Silica sand Pieces of broken glass Additive materials Finished mixture |
| Flow rate | 30-100 t/h |
| Total capacity of the system | 60,000 t/year |
| Accuracy of the dosing systems | ± 0.1% |
The charging into the weighing containers is implemented by means of finely controllable conveying conduit with maintenance-free magnetic drives.
Example: Recycling system
Recycling of large raw material quantities - heavy load conveying in wood processing
Large quantities of recycled wood are processed for chipboard manufacture with a manufacturer of repute in Germany. The delivered broken-up wood and pallets, however, whole logs as well, are loaded by scraping onto a conveying conduit from a wheel charger in quantities of up to 3t per blade stroke. With the highest level of availability under the most extreme environmental conditions, this provides for uniform loading of the downstream magnetic separator, which takes out the metal parts, and of a hacker, from which the entire manufacturing enterprise is supplied around the clock. With capacity of about 12m³, the conduit simultaneously serves as a buffer in the production schedule, if the hacker must be stopped on a short-term basis to manually remove residual metal parts. The further charging of the conduit can be implemented simultaneously.
In order to avoid overload of the motor through frequent start-ups and shutdowns with high loading, a frequency converter control was employed, that regulates the drive motor down to idle speed, at which no more material supply occurs, however an immediate run-up is possible at any time again.
Because of the high point and impact loading during the material discharge, a strong wearing plate was installed in the conduit and damper pneumatics were employed for bracing instead of coil springs.
| Material conveyed | Recycled and regular wood to 5 m length |
| Flow rate | 30 t/h |
| Drive | 2 Unbalance generators with 37 kW induction motor |
| Operating frequency | 650 min-1 |
| Vibration amplitude | 18 mm |
| Conduit dimensions | 9,000 x 1,300 mm (LxW) |
| Total weight | 10,000 kg |
| The drive by means of unbalance generators with steady-state electrical motor is particularly suitable for large and heavy user devices. |
|
