DUMA GmbH

The German company Burghardt & Schmidt GmbH, Remchingen-Wilferdingen, placed an order with DUMA Maschinen- und Anlagenbau GmbH, Duisburg, to build a technically outstanding electrostatic oiling machine.

The machine is executed in stationary design, whereupon the specific technical requirements of the customer’s equipment have to be considered.

Depending on the production quality one out of 5 different oil types are applied. The machine will be executed as heated version, as also flow inhibited oil types will be used. This implies filling of the double walled machine housing with thermo oil. Heating of thermo oil warms up the machine walls so that flowability of the processed oils is guaranteed. Besides, temperature of all components for oil supply such as filters, valves, pumps, pipings etc. is maintained to keep up flowability of oil.

As the machine will be installed in front of the recoiler of the slitting line a threading car is used. The DUMA oiling machine is designed in such a way that the threading car including strip may pass the oiling machine completely.

For this purpose the machine housing is constructed with an enlarged strip opening in U-shape, not only for passage of the threading car but also to raise the car rails within the machine depending on the threading position of strip.

To provide enough space for the rails within the machine housing, the upper spray bar can be moved upwards as well so that its final position is located above the rails.

The enlarged opening of the machine housing is equipped with swivelling metal doors respectively metal flaps to guarantee a trouble-free and unpolluted oiling process. After passage of the threading unit and before start-up of oiling these doors are closed again. The substantial engineering to control the doors/flaps necessitates a significant redesign of the inside machine housing.

After passage of the threading unit the oiling process is started. During oiling the threading unit remains in standby position. As soon as the oiled strip has completely passed the oiling machine, oiling process is stopped and the threading unit returns to its starting position to pick up the next strip.

In designing this machine DUMA GmbH verifies once again its expertise in building electrostatic oiling machines for special applications.

Until 2008 the galvanizing lines of DUMA were equipped with edges masks operated via touch rolls. Those devices equipped with special, smooth-running air cylinders are operating very gently. Nevertheless, the touch roll may cause damages on the sensitive material especially of thin strips and higher line speeds.

For this reason DUMA has developed a contact – free edge mask. This edge mask is available in two different designs:

1. Retrofit kit for the mounting on an existing edge mask.
2. Full set of edge masks for replacement of existing edge masks or equipment for new installations.

The retrofit kit is erected on the existing edge mask.

Thereby an adjustable stop is operated by a servo drive. This stop limits the position of the edge mask. In case of a malfunction of the electronic equipment it is possible to maintain operation of the line as usual using the additionally existing touch roll. For mounting devices some minor adjustments to the mechanical, pneumatic and electrical equipment is required.

The full set of masks includes the electromechanical adjustment mechanism within the housing of the edge mask. Hereby the complete edge mask is replaced. The existing edge mask can be used as spare part further on. In this case, an adjustable stop limits the position of the edge mask and a customary operation via touch roll is possible. The advantage of the full set is the compact version.

The mounting of the retrofit kit is possible within a few days.