In most cases, a chocolate filler is required in order to produce chocolate. This filler can, for example, consist of chocolate, vegetable fats, nut paste and flavouring.

Before the chocolate filler can be processed, it has to be heated to the correct temperature. In this process, the filler is cooled under shear and then heated slightly. This ensures that it has a smooth texture and is stable in storage after it sets. The heated filler is poured into a block mould and then stored for a week at 12°C.

For further processing, the solid chocolate filler must be heated in a warming room at 28°C for approximately one week. After that, the soft block is homogenised and plasticised in a mixer with additives such as nuts or raisins. This mixture is now fed into the extruder, a task often performed manually by mobile transport containers. Finally, the chocolates are injection-moulded on a conveyor belt by the extruder, coated with chocolate and decorated, then cooled and finally packaged.

Using KNOLL technology, it is possible to process solid chocolate filler even at 12°C and to eliminate the warming room and the holding time from the process. This makes the production process more flexible, timesaving and efficient.  There is no longer any need for long transport routes between the cooling and warming rooms – and for the warming room as such. One of the important factors here is that the system is a fully integrated, closed-loop system which meets the highest hygiene standards. It is also worth highlighting the possibility for continuous production where previously only batch mode production was possible. Given that KNOLL pumps deliver high pressures, even large distances can be bridged. On the pressure side, solids such as nuts and raisins are admixed homogeneously on the conveyor line by static mixers.

Depending on the how chocolate products are produced, KNOLL can provide the manufacturer with an optimal solution which will streamline – or even bypass – time-consuming stages of production.

The pumpkin harvest takes place in the autumn.Processing of the pumpkin harvest takes from October until December, a phase described by the producers as the “pumpkin drive”. 
The customer previously used a rotary piston pump manufactured by a well-known US manufacturer for the further processing of pumpkins.
Even though the pumpkins were shredded, boiled and thoroughly cleaned prior to processing, tiny particles of sand still cling to their skins. The abrasive properties of the sand grains make pumping very difficult for the radial piston pump.
Since both the housing and the piston in these pumps are metallic, the sand particles act like sandpaper on the metallic components of the pump and wear out the inner workings of the radial piston pump within just 72 hours.
During the so-called drive, manufacturers of pumpkin cream incur enormous costs due to the high rate of wear and tear on the radial piston pumps. To reduce these costs, a KNOLL progressing cavity pump is now being used in place of the radial piston pump.

KNOLL uses a standard type MX30S-60/10 pump for this application.
Thanks to MX EvenWall® Technology, which provides exact and even pressure between the ductile coated stainless steel rotor and the soft elastomer of the stator, the MX offers many advantages in this field of application.
The closed pressure chambers of the KNOLL pump prevent medium from flowing back into the lower-pressure chamber (eliminating jet abrasion). This has two advantages: firstly, it allows very high operating pressures to be used and, secondly, the abrasive particles effectively have no chance of damaging the pump surfaces. It also allows the pump to be better primed with up to 100 mbar of absolute vacuum.
A further advantage of a KNOLL progressing cavity pump is that it is easy to clean.
A MX can also be operated filled with water, thus enabling the pump to clean itself. This also allows the remaining pumpkin mix to be pushed out of the pipes in order to clean the pump system and piping. This means that the MX is capable of achieving the same high pressures with water as with high-viscosity media. During cleaning, it is important that RPM can be regulated. Using the MX, pump speed can be regulated in stages from 1 to 20 as standard.

A radial piston pump, on the other hand, can only build up a low pressure when running at low RPM and using low-viscosity media. Backflow into the preceding pressure chamber cannot be prevented because the pressure chambers are not closed. A “buster pump” is needed for cleaning because a radial piston pump cannot clean itself or the piping.

The KNOLL progressing cavity pump was used for the first time midway through a pumpkin drive. At the close of the pumpkin season, the pump was examined at our factory. It had been in use for approx. 1-2 months and exhibited minimal sign of wear and tear.
The KNOLL pump has now been in use for 2.5 pumpkin drives. For the producers of the pumpkin cream, the extended life of the pump is a major boon as it cuts costs significantly and allows many processes to be simplified.

A solution for reducing, pumping and plasticizing young to medium-aged cheeses has been found by using the KNOLL type MX50R-60/30 progressing cavity pump in combination with a frozen block cutter.

The firm to very hard blocks of cheese, which weigh as much as 30 kg, are reduced to a pumpable size of 25 x 35 x 20 mm by the reducer and conveyed through a feed hopper adapted to match the frozen block cutter outlet, and directly into the MX pump system.

The feed screw on the feed hopper pump has a special non-stick coating which prevents cheese from sticking to the feed screw and so provides for a smoother conveying process.

This coating has other advantages too, as it allows the feed screw to be cleaned more quickly and easily.

Plasticizer plates built into the discharge nozzle or at the end of the pressure line shape the cheese into narrow strips, thus speeding up and simplifying subsequent processing. The Even Wall® geometry is a key factor here because it allows pressures of up to 80 bar to be used.

An existing progressing cavity pump was replaced with an MX pump by KNOLL by optimising a production process. With this application, grease is pumped at temperatures in the 100 – 200 °C range and at a viscosity of approx. 10,000 mPas. The process is such that it is possible for clumps of grease to arrive at the pump despite the high temperature and the liquid properties of the medium.

In this case, an MX50R-60/10 with bridge breaker and separate drive was used in order to prevent bridging. Taking account of the medium’s complex properties, the bridge breaker ensures controlled and troublefree delivery of the low-viscosity grease.

The universal joint runs in needle bearings lubricated with heat-resistant lubricants and, thus, is suitable for applications involving temperatures up to 250 °C.

Given the customer’s pre-existing machine set-up, the current pump’s connecting dimensions were adapted to match those of the MX pump, both at the feed hopper flange and at the pressure connection. This enabled Knoll to provide the customer with a more simple and, above all, more efficient refit.

For this application, an MX50R-80/20 with an electric heating jacket and dry run protection was placed below a vacuum mixer. The MX is used as a mixer discharge pump and fills the drums with adhesive under vacuum. A vacuum of 20 mbar absolute is maintained in the mixer. In this process, the filling time of the moisture-reactive adhesive including 800 µ filtration is about 4 minutes per drum.

The feed housing and the conveyor worm of the progressing cavity pump MX from KNOLL have a special nanotechnology-based non-stick coating to avoid unwanted bonding effects and bridging. Due to the highly abrasive properties of the medium and high viscosity values ranging from 700,000 – 1,500,000 m Pas, a solid stator made of a specially hardened material is used for this pump. The KNOLL solid stator uses the tried and tested “half-shell system” employed in the production process for the KNOLL screw spindle pumps type KTS.

The pump was tested for vacuum tightness for a week prior to delivery, and it was found that the high vacuum level remained absolutely constant. 

In this specific application, our competitors’ pumps achieved a maximum life of only approx. 3 months and showed the first signs of wear after only a few weeks. The MX by KNOLL Maschinenbau GmbH has already been in use for more than a half year and so far has not shown any signs of wear.

Austrian foodstuffs manufacturer Agrana is the European market leader in the field of biological fruit preparations. Here, research and development play a key role, both at product level and in the production processes themselves.

The MX by KNOLL Maschinenbau was used on a trial basis as part of a new fruit processing concept and produced an impressive all-round performance. The task was to collect and convey various fruit varieties in a still frozen state.

A heated MX30R-60/10  was used for the test setup. Its trough-like shape prevents build-up from occurring on the hopper walls while the tapered worm conveyor ensures optimal product removal from the hopper floor. The CIP-compatible axial face seal with torque transfer element facing away from the product allows easy cleaning while intelligent joints make for fast dismantling. By way of an option, an additional extension hopper can be adapted.

The tests at Agrana showed that the MX provides reliable transportation of various fruit media from starting temperatures as low as – 18 degrees (Celsius). It was able to feed the partially still deep frozen fruits directly into the pump. The media were, as planned, reduced by the MX in a controlled way while being conveyed.

The case study shows that the feed hopper pump version of the MX eccentric screw pump is able to effectively support innovative production processes in the foodstuffs industry. The MX is a good choice when it comes to implementing new formulations or new production methods in a way that maximises sustainability and efficiency while ensuring the gentle processing of natural base products.

In this case, a viable alternative would be to use PTFE (Teflon) both in the secondary seals and in the stator. KNOLL Maschinenbau recently assembled an MX20 for a south German paints manufacturer to meet its special requirements of suitability for use in paints production and frequent cleaning with a mixture of solvents. Given that these solvents are recycled, their composition and concentration may change, but this must not alter the properties of the eccentric screw pump.

To this end, the MX20 was fitted with a solid stator made of Teflon. The excentric movement of the rotor is compensated by a titanium torsion bar. No elastomer seals are used. As a result, the MX, first, has the required level of resistance to cleaning with solvents and, second, retains its KNOLL trademark properties:

1. High ease of servicing even when using non-standard components;
2. Good cleanability (CIP and SIP);
3. Excellent pump characteristics (low pulsation, high pressures, suitability for high viscosity levels).

In the case of this special version, attention was also given to preserving the modularity of all key components so that the paints manufacturer can, when necessary, adapt the pump to changing conditions within the manufacturing process.

All in all, this MX20 is a great example of how KNOLL Maschinenbau responds flexibly to its customers’ needs to facilitate their manufacturing processes as best possible.

PROCESS EXPO is the premier worldwide trade show for leaders in the food and beverage industriy. At this fair, all is about sanitary installations.

 KNOLL will present the new developed double spindle pump DSP as well as the different MX-pump sizes. Of course, all important special versions of MX are shown: the hopper version and the submerged version.(to unload drums)

We are looking forward to your visit.

One of the main goals while constructing this pump was an easy service on all components. As a result the maintenance of each MX is simple to carry out, which leads to a long running life and low life cycle costs.

Current information on the DSP is in the product presentation that you can download from here: