Lödige at Chem Show 2017: Tablet coater in a new design
PADERBORN – September 5, 2017 – Gebrüder Lödige Maschinenbau GmbH developed a series of innovations in the field of coating technology for the pharmaceutical industry. The LC series of coaters, specially conceived for coating tablets, has been the subject of extensive redesign. For example, a newly configured airflow now provides a significant boost in efficiency and availability of the machines. Advanced sensors facilitate optimization of the spraying and drying process, and simple and safe adjustment of the nozzle arm makes handling easier. As the latest member of the LC coater family, the LC Lab was specially developed for use in the laboratory.
With the newly configured air flow, Lödige has significantly increased the throughput capacity for tablet coating. In contrast to the previous forced air feed via an intake boot, the air to the LC series of coaters flows through an air injection manifold over a large circumference of the coater drum in the direction of the tablet bed. This enables even, largely turbulence-free entry of a large volume of drying air into the drum. The innovative concept ensures a high drying capacity and hence high spraying rates.
The undesirable effect of spray drying, resulting in spraying losses during coating, is effectively prevented. This not only extends the intervals between the cleaning procedures; it also significantly reduces cleaning effort. If cleaning is necessary, this can usually be carried out simply and economically, even in the case of highly effective products, with an integrated WIP or CIP system.
Reliable thanks to new sensors
Accurate spacing of the nozzles from the tablet bed is critical for optimum spraying results. To accomplish this reliably and simply, the LC series of coaters was equipped with new features: a laser distance sensor carries out the required measurement. The nozzle is subsequently adjusted from the outside by means of a hand wheel. Thus, the operator is – in contrast to previous solutions – not required to reach into the coater. As an option, distance measurement and adjustment can be performed fully automatically. The correct distance is thus adhered to during the entire spraying phase.
When it comes to product temperature, Lödige sets great store by precision. Normally, it is determined by exhaust air temperature; however, the latter responds rather sluggishly. Due to the high relevance of product temperature for the drying process, the Paderborn experts opted for an additional solution. An infrared sensor takes a measurement directly beneath the spraying zone. Precise measurement guarantees that the film-coated tablets do not cool down during the spraying phase.
High-performance, small scale: the new LC Lab laboratory coater
The new addition to Lödige’s LC series of coaters is of modular design and can be equipped with the individual modules needed for the coating process or specific application.
The engineers oriented the design of the coater fully to requirements in the laboratory – starting with the choice of material for the housing. The latter is made of Corian. The FDA-compliant composite material with outstanding hygienic properties offers a whole series of advantages, particularly in the laboratory. It is easy to clean, resistant to solvents as well as impact-, scratch- and wear-proof and permits a joint-free finish. Seams that are problematic from a hygienic point of view were thus avoided from the outset in the LC Lab.
Simplicity of handling has been consistently pursued with the LC Lab. For instance, the utilizable volume of the entire drum can be halved with ease while retaining the drum geometry. This is made possible by a specially developed, convex partitioning screen and segmented nozzle arm. Trials with cost-intensive materials can thus be initially carried out with low product deployment and the results then applied to larger batches.
The nozzle arm was adapted to laboratory needs in cooperation with the experts of Düsen-Schlick. Two standard high-performance nano nozzles are used. These ensure optimum nebulization of the coating fluid, even at low spraying pressures. Four nozzles are optionally available for demanding applications. Due to the use of plastic and titanium, the nozzle arm is particularly lightweight and easy to handle.
The innovations introduced by Lödige for the commercial LC coater also offer advantages for the smaller LC Lab. The nozzle arm and its position can be reproducibly adjusted by the operator from the outside and thus geared to product- specific changes to the tablet bed during the coating process. The new low- turbulence supply of drying air flow also ensures an optimum drying process with the LC Lab with minimum spray drying and dust build-up on the nozzles.
Lödige at Chem Show (October 31st – November 2nd, 2017, Javits Center, New York): Hall A, Stand #818
Contact for readers’ enquiries:
Gebr. Lödige Maschinenbau GmbH
Elsener Straße 7-9 – 33102 Paderborn, Germany Tel.: +49-5251-309-371
E-mail: firstname.lastname@example.org www.loedige.de
Müllerstraße 27, 80469 München