Along the pretreatment line of a hot dip galvanizing plant, conditions are difficult: workpieces have first to be cleaned in diluted hydrochloric acid to ensure that they are as clean as possible. As a result, the hydrogen chloride content of the air along the pretreatment line is around 2 per cent. This means that the indoor crane and the components on to it are subjected to exceptional acid exposure. Plastic energy chain systems have been proving their worth in the energy supply to the process cranes at Wiegel for several years. They move in plastic troughs made of the chemically-resistant material igumid EG+, which enables the system to easily cope with the aggressive conditions.
In the past, cable festoon systems were used in the pretreatment line of Wiegel's hot dip galvanising plants. Cables and hoses were suspended and moved on small trolleys. A disadvantage of this technology, however, is that at the end of the travel, a cable station takes up a lot of space and for this reason the space of the pretreatment line cannot also be completely sealed off. The rollers of the cable trolleys also fail after some time, because the C-profiles in which they are guided become corroded and sharp-edged due to the acid exposure. As a result, the rollers quickly wear out.
The project management of the technology department at Wiegel Verwaltung GmbH & Co KG decided at this point in favour of polymer energy chains from our product portfolio, which offered the customer two advantages above all: a tight-sealing solution for the area of material preparation, which was previously not the case with a festoon system, as well as high wear resistance.
The first energy chain was used in a Wiegel plant in 2015. The next application followed a year later, where we supplied both the E4/4 series energy chain and the new plastic trough made of the chemical-resistant material igumid EG+. This ensures a high resistance to chemicals, so that the use of the guide trough is ideal for use in hot dip galvanizing or, for example, fertiliser production. The igumid EG+ is characterised by very low water absorption. This offers increased resistance to aggressive chemicals. The material can be used in a temperature range of 0 °C to +100 °C with its clearly optimised sliding properties for the guide trough and also for most series of e-chains. Since both the e-chain and the trough in the complete system consist of the chemically resistant material, they are very good gliding partners.
So far it has become clear that the energy chains from igus are working well and reliably at Wiegel. "The experience gained since 2015 shows that the use of an acid-resistant energy chain in the area of the pretreatment line for energy and signal transmission was the right decision", concludes Ronny Horn, Project Manager at Meissner Krane. "In all factories, the systems have been running trouble-free since their commissioning." And Peter Zorn from Wiegel adds: "The plastic trough was very important to us. Neither 304 nor 316 stainless steel would have withstood these environmental conditions. Equally important to us was the fact that the wall around the pretreatment line can now be completely closed and we also have much less maintenance with the new system." These requirements have so far been fully met. Energy chain systems from igus will also be installed at the next Wiegel plants that will be retrofitting Meissner cranes.