Furnaces for preheating transformer moulds and curing transformer gap filler
When manufacturing high-tension transformers, it is necessary to first preheat the transformer moulds and then cure the gap filler. The line for manufacturing them is made up of a preheating furnace and a hardening furnace. These are continuous furnaces with a chain conveyor, divided into multiple heating zones. The furnaces have forced air circulation.
The line’s operation is fully automatic, controlled by a programmable Simatic automated system that communicates with and is subordinated to the customer’s control system. This line’s enormous advantage lies in its fully automated transformer production, eliminating the need to manipulate the charge between individual operations. The transformers are laid into the gap-filling machine by robots, and so we also designed these furnaces so they would tie in to the manipulation mechanisms in the interim steps. Through this line’s automation we have eliminated human operator interventions and thus increased the quality of production.
The customer required above all an even temperature distribution in the furnace, due to the gap filler, which has utilisation conditions set by the manufacturer so as to achieve the required characteristics. Meanwhile they needed the hardening furnace to be able to reach different temperatures in its individual zones. One fundamental problem we had to solve was automatic manipulation of the parts between the preheating and hardening furnace, with no human intervention.
We achieved the required ± 3 °C temperature distribution via powerful air circulation, and achieved the differing temperatures by dividing the furnace into the necessary number of heating zones. To fulfil the last requirement we used special manipulators for reliable and precise part unloading and loading. Precise positioning is important because a robot manipulates the parts. Also, thanks to the line’s automation, we managed to increase the production quality and thereby its capacity and shortened production times compared to the original solution. We also tailored the line to the customer’s requirements so as to minimise space requirements.
What’s great about this facility
- met the requirement for a ± 3 °C temperature distribution
- automated the production process
- increased production capacity and quality and shortened production times
- divided the furnace into multiple heating zones for precise maintenance of the transformer production process