The KBK concept is a well-rounded package
Precision and ergonomics in zinc casting
KBK closed-circuit monorail transports molten zinc at Karl Wagenaar GmbH & Co. KG
Karl Wagenaar GmbH & Co. KG started in 1972 with five employees in Heiligenhaus (Rhineland) as a contract grinding shop. The company purchased its first die-casting machine in 1980 and relocated to the neighbouring town of Velbert three years later. Production has been gradually expanding ever since. Now, around 100 employees produce zinc die-castings seven days a week in multi-shift operation for all branches of industry, primarily for the construction and the lock and fitting industry. About 5000 t of zinc are cast per year.
The completed production expansion increases capacity from three to four pre-melting furnaces. The molten zinc, which has a temperature of 420°, must be transported efficiently, quickly and safely from the four furnaces to the 26 die-casting machines.
Up to now, the company’s own-design equipment with double-T-girder and travelling hoist did its job. Power was supplied by trailing cable. For the employees, this meant that for travel on curved track, the power supply had to be laboriously disconnected and reconnected before and after the curve using plug-in connections. There was always a risk that the temperature of the molten zinc would drop, rendering the batch unusable.
When planning the new production hall, factory manager Christian Schwab and foundry manager Recep Tunc therefore considered it important to optimise the supply of material to the installations. The vision of the two planners was clear: a smooth-running and push-travel monorail circuit with continuous power supply. One idea for an automated system was rejected in the planning phase. The risk of a too long downtime for multi-shift production is too high and safety aspects can be better ensured with manual operation.
The steelwork company Uta Kaminski was finally commissioned with the planning and execution of the monorail circuit. Both companies work as neighbours in Velbert and maintain good business relations. The implementation of the new transport system was driven forward in cooperation with Demag.
The KBK monorail system enables 26 die-casting machines to be fed with molten zinc from four pre-melting furnaces. Thanks to the modular design of the Demag KBK crane construction kit, it was possible to manufacture the straight sections and curved sections of the monorail circuit in accordance with customer requirements.
Two manual Demag trolleys move the transport furnaces along the almost 87-metre-long monorail circuit. The combination of cold-rolled profile sections of outstanding rigidity and low deadweight and trolleys with plastic travel wheels featuring anti-friction bearings enables employees to move the transport furnaces, each with up to 500 kg of molten zinc, smoothly.
The integrated busbar line in the KBK II R profile section enables continuous transport of the load, even along the two 90° curves.
Buffer trolleys avoid the risk of overloading the suspensions if both transport furnaces move along the same track section. In addition, the number of suspensions was doubled to increase the safety standard further.
Interview with Christian Schwab (factory manager)
Karl Wagenaar GmbH & Co. KG
Demag: Mr Schwab, why did you prefer the Demag solution?
Christian Schwab: We have been working closely with our steelwork producer Kaminski for years. During the planning phase, my colleague, Mr Tunc, and I looked at some possible solutions together with Mr Kaminski. Demag impressed us, above all, with the integrated power supply system. This enabled us to overcome the weak point of our own design, which we had previously used.
We also pay attention to where we buy. Thanks to the proximity of our steelwork producer and the direct line to the Demag sales department, we can be confident that we will receive support and spare parts for the monorail circuit in the event of an emergency.
Demag: Which advantages speak for the Demag products used?
Christian Schwab: For one thing the new monorail circuit is smoother and the transport furnace is easier to move for our employees. Transfer of the molten material to the machine furnaces is easier.
Furthermore, the integrated busbar line is, of course, the greatest advantage. The trailing cable is no longer required and the transport furnace can thus be moved continuously, even during travel on curved tracks. This improves the transport process and we can avoid temperature differences in the zinc.
Demag: What impressions have the employees conveyed to you so far?
Christian Schwab: So far I have not heard any negative comments! I take this as a good sign and emphasise that we are completely satisfied with the new monorail circuit.
The integrated power supply line ensures safe and space-saving energy transfer. Any possible collision is avoided thanks to the cable-free design. The customer’s employees can move the transport furnaces along the entire length of the monorail circuit and concentrate fully on working with the molten zinc. The KBK crane construction kit enables the customer to achieve the required track layout and it can be extended as required. In addition to straight and curved sections in various lengths, track switches and turntables can be used as expansion options, as can electric trolleys or subsequent partial or full automation. The smooth running characteristics of Demag components enable fast and safe handling and, at the same time, exact, effortless positioning of loads. In this way, the light crane system ensures effective work processes and can increase productivity.