Knoll Maschinenbau GmbG

Archive for: 2011

Reducing, pumping and plasticizing blocks of cheese with the KNOLL MX

A cheese dairy from the Netherlands has been making a variety of finest-quality cheese products since the early 19th century, and has meanwhile made a name for itself as the leading Dutch brand world-wide.

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.

Preventing bridging with the MX50 feed hopper version

KNOLL develops, designs and produces solutions customised to the specifications of its customers. These include one of the world’s leading oil companies, which has successfully been using KNOLL progressing cavity pumps for several years now.

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.

Processing adhesives with the MX vacuum pump

A well-known Swiss adhesives manufacturer is an important supplier to the international automobile industry of glues for bonding car bodies, windscreens and dashboard kits. Air trapped in the adhesive would allow gaps in the sealing contours, which in turn would result in leakage inside the vehicle due for example to the ingress of rainwater through the windscreen. The adhesive must therefore be absolutely free of trapped air in order to ensure a continuously tight adhesive bead. For this reason, the adhesive is manufactured under vacuum and delivered to automobile manufacturers in vacuum-sealed drums.

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.progressing cavity pump with solid stator

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 16 months and so far has not shown any signs of wear.

Pumping frozen fruits with the feed hopper version of the MX30

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.

Agressive media and a robust pump

There are applications, e.g. in the chemicals industry or in the paints and lacquers industry, where elastomers cannot be used. Pumps would be susceptible to chemical attack, particularly when using mixtures of different solvents. Therefore, not only the medium itself but also the cleaning process must be taken into consideration when designing the pump.

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.

KNOLL at the PROCESS EXPO in Chicago

From November the 1st until 4th 2011 the exhibition PROCESS EXPO takes place in Chicago, Illinois. KNOLL exhibits in the North Hall, booth 848 – you are invited to visit us at our booth.

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.

Extremely Easy to Service: KNOLL’s Progressing Cavity Pump

Progressing Cavity Pumps often range as the first choice when it comes to handling abrasive or highly viscous media. However, they depend on the reputation of causing long downtime in service because their components are complex and difficult to access. In the case of the MX from KNOLL Maschinenbau this is not true, as the following videos show:

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.

Interpack Trade Show: What KNOLL will exhibit

From 12 to 18 May 2011 interpack trade show will be held in Duesseldorf (Germany). KNOLL Maschinenbau will be participating, our booth can be found in hall 4, stand 4E05. You are cordially invited to visit our booth. Pumps from KNOLL do fit very well to the “world’s most important trade fair for the packaging sector“, as it adresses also all things processing.

The wider focus on processing issues is of interest for companies in the food and beverage, pharmaceuticals and cosmetics. It offers a holistic view on the process chain featuring all aspects on processing, metering and finally packaging.

KNOLL Maschinenbau will introduce its new double spindle pump DSP. In addition, the pumps of the MX-series will be shown, including a new feature on the drives: a MX10 with stainless steel drive. Of course, all important models of the MX will be presented, too. Among them a version with double jacket for temperature control, a hopper version and of course a submerged version (for tank drainage).

All in all it may be worthwhile to stop by at KNOLL Maschinenbau in hall 4. You are very welcome and we look forward to meet you at interpack in Duesseldorf!

Pumps for Waste in Food and Beverage

Producing food or beverages implies the handling of waste. Of course waste must be routed quickly and safely to external disposal or rework purposes. As an alternative to conveyor belts or compressed air as means of transportation the progressing cavity pump from KNOLL Maschinenbau can be used, too.

This pump can be used even if the medium is relatively dry. A Spanish producer of fruit juices was looking for a solution that could help him to transport the peel of citrus fruits. The MX from KNOLL Maschinenbau as a hopper version was exactly what he was looking for: Service life got considerably longer compared to an earlier setting with a different pump.

A particular challenge was the fact that the pipeline from the hall into the open is very long. The pump therefore has to provide sufficient pressure  in order to transport  the peel (mostly from pressed oranges and lemons). In this case a MX50R-60/30 with large hopper and corresponding feeeding screw is used. This pump coveys 5 t / h at a back pressure of up to 25 bars.

It is fully made in stainless steel with FPM elastomers and a universal joint which is provided with a sanitary seal. Its conical feeding screw empties the hopper efficiently. The trough shape prevents deposits on the hopper walls. In the pumping tunnel an overfeed ensures the optimal filling of the chambers in the pump assembly. Of course the MX in this version is fast and easy to clean, as any other version of this series.

The Spanish beverage company is very pleased with this pump and confirmes, after several years of use, that KNOLL Maschinenbau had not promised too much. Also, the projected maintenance interval of 5 years in this sense is not an empty promise.

High Back Pressure Shows the True Abilities of a Pump

Modern pumps have many capabilities and still face ever growing standards. Among them ranges the careful transfer of media at high pressures. This requirement not only targets transfer pumps managing large distances but also metering pumps, for example when these lead into spray heads with fine nozzles.

The MX-Pump from KNOLL Maschinenbau takes to high pressures like a duck to water. This progressing cavity pump can easily deliver pressures of up to 80 bars while promoting its media so gently that lumpiness like cooked fruit or pieces of vegetable are not damaged. With its outstanding pressure stability the MX covers a wide range of capacities. For very high flow demand the MX100 delivers up to 200,000 liters or 200 m³ per hour.

Of course, piston pumps fulfill these tasks, too, but at the cost of very high pulsation, high pressure peaks and shear forces that can damage the media. In contrast the MX as progressing cavity pump works with extremely low pulsation which brings an especially smooth transport for the medium and ensures accurate metering without valves.

Due to its special stator geometry in EvenWall® this progressing cavity pump from KNOLL Maschinenbau comes in a much shorter length compared to pumps from competitors, so that it fits very well even under the condition of tight space. In addition considerable energy savings are possible because less pressure levels are required for the realization of high pressure. Wiht each pressure stage of the MX-Pump a pressure of 10 bars is available.

Another advantage of the MX is its excellent service friendliness which applies as well to high pressure versions of this pump as to all others. For very large versions of the MX KNOLL Maschinenbau offers special service tools for dealing with the heavy equipment. Short downtimes are guaranteed, so that these pumps offer high efficiency.

As a final point the modular design of the MX has to be mentioned here, as even under the requirement of high pressures an adaptation to different pump assembly versions is possible. So the MX-Pump can be individually adapted to different application scenarios, even under very different conditions, without any problems. Its compact design (short length) remains, of course.

Overall it is no wonder that this progressing cavity pump increasingly gets known for use cases under highly demanding conditions, as for example high back pressures. Renowned plant engineers have therefore already converted their product portfolio to this pump.