Multi-disc peelers (MSS)

Individual setting options



Practical information on working with Multi-Disc Peelers (MSS) when peeling tubers, root vegetables also onions
and fruit



Lots of varieties of tubers, root vegetables and fruit can be peeled with the machines. The natural product must, among other things, have a certain level of firmness. Not all, but many natural products can be peeled with the machines. Below, we have listed a series of options that can influence the peeling result.



A.        The options of changes (in the settings) of the machines


            The peeling result of the above-mentioned machines can be influenced by


1.         the input quantity(degree of filling),

2.         the speed of the peeling discs,

3.         the speed of the transport mechanism,

4.         the fitting of blade or carborundum, onion  or special discs to the machines.


      When using carborundum peeling discs (5.), the type of grain on the discs can
      also influence the peeling result:


            5.1      fine,

            5.2      medium-sized,

            5.3      coarse grain or

            5.4      other grain.


When using blade discs (6).: Further influencing of the peeling result is possible
by means of adjusting the blades (approx. values) on the blade discs (available with two or three blades):


6.1            0.4 mm,

6.2            0.5 mm,

6.3            1.0 mm,

6.4            1.5 mm

6.5            or other dimensions.





And by altering the height of the throw up rubbers by replacing the platelets
            to which the rubbers are affixed.



6.6            0.0 mm,

6.7            0.5 mm,

6.8            1.0 mm,

6.9            1.5 mm,

6.10        2.0 mm,

6.11        2.5 mm,

6.12        3.0 mm

6.13        or other dimensions.


7.                        Onion peeling discs
If the machine is used as an onion peeling machine (-Z), different discs are fitted into the machine:


7.1          Scoring discs with vertical scoring blades, approx. diameter 135 mm,

7.2          Carborundum discs (with fine, medium-sized or coarse grain size, approx. diameter 135 mm,

7.3          Cleaning discs with throw up rubbers (see 6.6 to 6.13), approx. diameter. 135 mm

7.4          Blade discs. Depending on the quality of the raw produce, blade discs with 2 or 3 blades can be used (see 6.1 to 6.5) and throw up rubbers (see 6.6 to 6.13). Diameter of the discs is approx. 150 mm.


The discs are generally fitted as described below:


a.  First about 6 scoring discs,

b.  then the carborundum discs indicated (normally 12 of them),

c.  then the cleaning discs (4 of them).


The discs can be arranged differently and blade discs can also be inserted (see 7.4) if required.



If onions are peeled, they must first be topped and tailed either by hand or by machine. See the possible options provided by Dornow for this purpose online:, D.-15.11.



  1. Special discs must be individually adjusted if possible.


On the basis of the above, it is clear that there is a wealth of possibilities to adjust
the machines to the product you wish to peel.



B.        How do you carry out the changes to the settings/supply?


Re 1.  You change the speed of the regular and controllable feed-in hopper con­veyor until you obtain the best filling degree of the machine. The product must be able to move freely in the machines. Too many products in one section of the machine may result in unattractive flat peeling, no peeling or irregular peeling. Too few products could damage each other or display other negative conse­quences. When filling the machines - not via a belt but by hand - more or fewer goods must be placed into the machines in line with the requirements.


Re 2.  The speed of the peeling discs can be changed by turning the appropriate button of the control panel (= changing the frequency, the Hertz value  = frequency control).


Re 3.  Changing the speed of the transport equipment: see Re 2. (above).


Re 4.  The peeling lines are pulled out of the machines and the blade peeling discs are removed/replaced by rotating them (by hand, wearing gloves). Combi­nations of peeling discs can also be screwed on (e.g. first carborundum peeling discs, then blade peeling discs or vice versa).


Maintaining sharpness through cleaning: A brown film may develop below the blade that could creep up as far as the cutting edge of the blade (= insulation of the sharpness). Let it dry. Remove with a chisel. - Grinding the blades: Leave on the disc. Using a long kitchen knife sharpener grind very carefully from above and below without using any pressure.


Re 5. to 5.4. The grain on the adhesive carborundum films comes in various grain sizes ranging from coarse to very fine. Often, they are fitted in a graded way: first coarse, then medium-fine, and then very fine. All combinations are pos­sible!


Maintaining sharpness through cleaning: Let them not dry out over night! Clean immediately with a sharp, cold jet of water - no steam! Pores must not get clogged! An invisible, insulating film must not be allowed to develop over the grains! With pauses in production: Briefly hose the rotating carborundum discs in the machine down with a cold jet of water!


Re-applying the carborundum films: First, if present, remove the carborundum films from the aluminium disc by means of a sharp tool. Lift off the carborundum film from the aluminium disc. Throw away this used carborundum film. Thor­oughly clean the aluminium disc. No grease residues! Then warm this disc up to about 50°C.

New film: Peel the paper off the adhesive layer. Then stick the carborundum film on and press it down forcefully for a long time (you may have to press it down with a heavy object). Beforehand: Make sure that the steel wire on the aluminium disc fits into the groove of the film.


Re 6. to 6.5. The blades can be shifted: unscrew lock screw. Using a hex or Allen key, raise or lower the blade. When the blade is in the right position, tighten the lock screw. Adjustments from 0 to approx. 1.5 mm are possible!


Cleaning and grinding of blades: see above


Re 6.6 to 6.13. –Throw up rubbers, fixed onto screw-on steel platelets. - These rubbers are responsible for creating movement — even turbulence — inside the machine. Their height has to be adjusted to suit the product. The product should be able to move and turn in the machine so that it is peeled all over. There are normally 3 rubbers on one peeling disc. They can have different heights: some examples: 1 – 0 -0 or 2.5 – 2.5 – 2.5  or 2 – 0 – 1 mm.


Re 7. A comment is made in point 7. "Onion peeling discs" above regarding the installation of suitable discs for onion peeling.



C.        Small trials in the machine


One can, for example, select 6 discs in the machine MSS-A (has one peeling line) that are located between the two plastic drivers. One can use these 6 discs as a trial track. Stop the drivers (safeguarding against all eventualities neces­sary). Using your hands, move the drivers a little during the peeling process in order to imitate the transport process. The products to be peeled are placed by hand into the machine onto the 6 rotating discs between the above-mentioned drivers. This is how trials can be carried out on small stretches of the line without using and activating the entire machine.



D.            Personnel

Particularly when there are many different varieties of fruit and vegetables to be peeled, specialist personnel with the ability to think proactively must be used. Precise records regarding production and trials should be kept.



Non-binding guidelines and recommendations!



A list of interesting articles and essays regarding the topics of the preparation and proc­essing of tubers and vegetables and associated specialist areas can be found at our Internet site at, Treatises. 







Review of your current peeling results or

before the purchase of a peeling machine or system:




Realistic test peelings with the most diverse peeling systems,

with the most diverse tubers and root vegetables, some fruit, with your raw produce are possible in our Peeling Test Center!









This paper contains non-committal notes. We do not lay claim to completeness. Alterations reserved.
Our order confirmation, accepted by our customers, is in effect upon delivery. - The presentation of a
new edition of this treatise will substitute for any previous versions.


Copyright by DORNOW food technology GmbH, D-40549 Düsseldorf





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