Against the background of performance optimisation, there is ever greater recognition of surface area as a valuable resource in all industrial sectors. Every square metre that cannot be used productively is a cost factor. For this reason, compact designs are increasingly sought after, even for machines. NETZSCH Pumpen & Systeme, one of the leading manufacturers of positive displacement pumps, has therefore now developed a smaller version of its proven T.Sano® rotary lobe pump for processes in which smaller volumetric flows suffice: the all-metal pump, which is specially designed for media that are demanding in chemical or hygiene terms, offers a pumping capacity of up to 8m³/h. The example of an Italian personal hygiene product manufacturer shows what is possible with this pump: the company has set the compact pump up on a trolley to enable mobile use. This means a saving in terms of additional technology as well as space.

The company is based in Northern Italy and its products include soaps and shampoos for various markets. The basic materials for this have to be conveyed from tanks to the manufacturing lines at 2bar with a flow rate of between 1m³/h and 6m³/h. However, the existing pumps needed so much space in the narrow passage which accommodates the connections that this not only impeded the installation itself but also any maintenance or cleaning work. The company therefore switched to a T.Sano® 08/8 from NETZSCH’s TORNADO® T2 series.

Small but beautifully made

Simply because of their special design, models of this type already need significantly less space than comparable pumps, without sacrificing anything in terms of performance. The reason for this is the belt drive which both drives the rotary lobes and ensures their synchronisation. Thanks to this dual function, no complex gear box is needed, and in addition the motor can be placed directly above the conveying chamber which means there is an extremely small installation depth. In the new smaller 08/8 version, which was created for applications where the priority is not high conveying volumes, the basic dimensions for width, depth and height only come to 305mm x 346mm x 630mm. For the soap manufacturer, whose previous pumps were more than 1m-long, that has meant a noticeable improvement in terms of the confined space.

In addition, the belt drive runs very smoothly, which reduces wear, and it operates completely oil-free, with the result that there is no longer any need for lubrication work. At the same time, it is considerably more robust in terms of damage or accidents than normal gear drives, especially as the toothed belt can be removed and replaced in next to no time, if necessary. In this way, maintenance expenditure and downtime are reduced to a minimum. The choice of materials also makes a contribution here: the T.Sano® only uses stainless-steel or other special steels for the housing and rotary lobes. The hard-wearing materials ensure a long service life and guarantee the pump’s long-term availability. Furthermore, both being oil-free and having a stainless-steel design ensure complete hygiene in the manufacturing process, a small pump with great powers of persuasion.

High performance and flexible application options

The rotary lobes are mounted using quick release taper lock ringsets outside the conveying chamber. This firstly makes replacement easier and secondly ensures the rotary lobes have only smooth surfaces on all sides. In combination with the interior, which is designed for optimum flow and to have no dead spaces, it guarantees problem-free throughput. A maximum of 8m³/h with back pressures of up to 10bar can be conveyed here, even with the small T2 model, irrespective of the consistency and viscosity of the medium. This specially shaped pump interior makes sure that the material can flow smoothly into the conveying chambers. This means pulsation remains at the level of multi-lobe rotors even with bi-lobe rotors, so that the medium can be transported without changing the consistency. In addition, the design makes it easier to clean the pump, with this being possible either manually or using the CIP process.

The Italian personal hygiene products company can therefore also use the pump flexibly on various manufacturing lines: its design enables very easy cleaning when there is a change of medium. At the same time, the compact form allows the whole machine, together with a frequency inverter to control the flow rate, to be accommodated on a trolley which enables easy transport of the pump to the next operating location. The first months of practical use have already shown that this solution has not only solved the previous space problems, but has also increased overall efficiency in terms of conveyance.