DESMA launches special machines for large-area seals

With a heating plate size of 2450mm x 1400mm, special seals for passenger car battery housings are produced on the vertical DESMA 968.700 Sealmaster. This large machine, with a total weight of 60,000 kg, has just been delivered to an internationally operating customer. It is equipped with two FIFO A injection units, each with an injection volume of 1000 cm³, which also have separate silicone stamping devices. The injection units can also be arranged in a shiftable way in order to be able to react flexibly to different gasket sizes. The "broadside arrangement" with 4 tie rods ensures good operability from two sides. Of course, corresponding shifting systems are also available as a shuttle system for 2 mould base plates. For this case, a corresponding platen heating system is then also provided in the outstation. The heating platens of the machine are equipped with up to 12 control zones per platen in order to achieve an exact temperature distribution even with different mould sizes. The clamping force of 7,500 KN is generated by 3 fully hydraulic pressure cylinders. The entire mould carrier was optimised by means of FEM calculation to achieve an optimum pressure distribution over the entire mould surface. With this machine size DESMA extends its special machine program for special seals by another size. For this project DESMA also realised a modular cold runner technology. Together with the FlowControl cold runner systems and the PressureSense technology, it is possible to react very flexibly to different spray volumes per nozzle. Furthermore, the hydromechanical QuickLock quick clamping system is also available for this machine size to make mould changes efficient.

DESMA 768.700 Sealmaster 

The machine is also equipped with the latest control system, the DRC2030TBM. Optimal utilisation of the 24" display ensures a full overview of the process, trend-based displays enable early fault detection and treatment, and the multi-touch function ensures simple and intuitive operation. The process visualization is also platform and interface for all SmartConnect products and additionally all DESMA automations can be controlled centrally.

Another special machine for the production of, for example, cylinder head gaskets is the DESMA TwinBenchmark. This special machine combines the advantages of a large clamping area with the good force application of a compact fully hydraulic clamping unit and the low operating height of the benchmark system. By using two pressure cylinders with one pressure introduction plate, the clamping force of 5000 kN is precisely transferred to the rectangular heating platen. Combined with rigid platens, excellent surface pressure is achieved over the entire parting line. The optional sliding device allows unobstructed access from three sides for manual operation and automation. Thus, the use of two mould bases is also possible in order to use the vulcanization time as manipulation time.

   DESMA TwinBenchmark

The DESMA 968.560 ZOZO with 560 tons clamping force is designed for the production of round sealing rings, therefore the heating platens in round design with a diameter of 1650 mm and radial heating zones have been specially developed. For a targeted closing force introduction into the article area of the seal, the optimum pressure distribution in the entire mould carrier area was optimised by an adapted and FEM calculated pressure introduction element. The machine is equipped with two flexibly adjustable injection units; the two injection nozzles can be moved exactly to the gate area and in this case replace the cold runner system. The result is low-waste article production.

 DESMA 968.560 ZOZO