1. 1
Optimize Strand
Pelletizing

2. BKS in a Nutshell
 For more than 25 years BKS is a leading [knife] service supplier in various
businesses such as Plastics, Recycling, Textile, Packing, Food etc.
 BKS pelletizing and pulverizing technology is a relatively new developed business
with the headquarter in Belgium [Lambermont] and a re-sharpening service center
in Malaysia.
 Our team of experts and the use of state of the art machinery offers manufacturing,
maintenance, modification, revision and [re-] sharpening of all wear parts for
pelletizing and pulverizing equipment.
 With know-how and experience of pelletizing and pulverizing technology BKS offers
customers added value.
 Our permanent search for optimal solutions, innovation and top quality guarantee
that our products and services comply above your expectation.
BKS, Beyond Expectation

3. Influencing Parameters
1. Kind of polymer, additives, fillers, quality and homogeneity.
2. Temperature and distribution in the strands.
3. Strand speed, number of strands and cross cut surface.
4. Corrosion and wear.
5. Cutting tool material choices and combinations.
6. Cutting gap adjustment.
7. Cutting geometry and helix of the rotor knife.
8. Re-sharpening quality.
BKS, Beyond Expectation

4. Model
To be able to make a quick and reliable check on the optimization potential
BKS developed a model, where we distinguish the influencing parameters:
A) Fixed
- The given situation [i.e. master batch]
B) Customer influenced
- Parameters the user can influence [i.e. cooling bath]
C) Service Supplier influenced
- Parameters the service partner can influence [i.e. re-sharpening]
BKS, Beyond Expectation

5. 1 - Polymer Characteristics
Fixed
The to be processed polymer is a given
Assuming we cannot simply change the material composition as most materials
are developed and engineered for their application.
BKS, Beyond Expectation

6. 2 – Strand Temperature
Customer influenced
Temperature and distribution of temperature in the strand
The higher the temperature of the strand, the less risk there is to break the material instead
of cutting it. On the other side pellets should not stick together after cutting. The temperature
is also determined by type of polymer, filler, additives and the handling of the strand before
cutting.
An important parameter of influence is the temperature homogeneity in the cross cut of the
strand. If the strand is cool on the outside but still hot [or even liquid] on the inside, negative
side effects like creation of dust, fines and shorter life time of the cutting tools will occur.
It is important to set up the granulation process in such a way that the strand temperature
is evenly divided over the cross-cut of the strand and as high as possible given the
circumstances.
BKS, Beyond Expectation

7. 3 – Strands
Customer influenced
Speed, number and dimension
The number of strands and their speed have a direct influence on the number of cuts.
The number of cuts per unit of time directly influences the life time performance of the
cutting tools.
Also the diameter of the strands influences wear generated on the cutting tools.
Improvement
Cutting material choice strongly effects cutting tool life time.
Optimal distribution of the strands along the cutting width extend cutting tool lifetime.
BKS, Beyond Expectation

8. 4 – Corrosion and Wear
Fixed
Customer influenced
Corrosion
Has an negative influence on the cutting tool materials and can be caused by polymer,
ingredients or contaminated cooling water. The cooling water quality can be influenced.
Wear
Has an negative influence on the cutting tool materials and can be caused by corrosion
and/or abrasive polymer or ingredients.
BKS, Beyond Expectation

9. 5 - Cutting Gap Adjustment
Customer influenced
Adjustment of the rotor- and bed
knife
The smaller the gap between the rotor and
bed knife, the better the cutting quality and
life time performance of the cutting tools.
The feasible adjustment depends on type
and accuracy of the pelletizer.
The optimal adjustment needs to be as precise [narrow gap] as possible
within the pelletizers limitation.
BKS, Beyond Expectation

10. 6 – Cutting Materials
Customer influenced
Service Supplier influenced
Material choice for of cutting tools:
Different cutting materials and combinations for bed- and rotor knives are available.
The polymer to be cut, corrosion and wear are critical factors to be taken into consideration.
Bed knife materials: Tungsten Carbide, Ceramics, Stellite or Diamond.
Rotor knife materials: Tool- and Stainless steels, Tungsten Carbides, Stellite
and Powder Metallurgical Materials.
The choice of cutting materials should be based on the circumstances and have an major
influence on the cutting- and life time performance.
BKS, Beyond Expectation

11. 7 - Geometry
Service Supplier influenced
Geometry and helix of the rotor knife:
The geometry [shape] and the helix of the
rotor knife teeth influences the cutting
behavior of the pelletizer.
Especially helix, rake- and relief angle have a
strong influence on the cutting performance.
[quality of the pellets & life time cutting tools]
Last but not least the final circular re-grinding
needs to be adjusted to the to be cut polymer
for optimal performance.
The best solution can only be found if user and service supplier work closely together.
BKS, Beyond Expectation

12. 8 – Re-Sharpening Quality
Service Supplier influenced
Re-Sharpening Service
Not only the geometry and the wear resistance of the cutting materials are crucial for
the quality and lifetime performance. The execution of the re-sharpening has minimal
similar influence and requires know-how.
The pelletizers construction, design/type of the bearing seat[s] and the quality level
of the maintenance have a direct influence on the concentricity of the cutting rotor.
This concentricity has a direct influence on the cutting gap, effecting the pelletizers
overall performance. Optimal bearing maintenance therefore is crucial.
BKS, Beyond Expectation

13. Summary
Conclusion
By influencing parameters - strand temperature and distribution
- cutting gap adjustment
- cutting materials
- geometry and re-sharpening quality
we directly influence the pelletizers performance and can
control Maintenance, Repair and Overhaul costs.
Recommendation
Execution of this model is easily applicable in every strand pelletizing production facility.
Gained information should be shared with your service partner which will result in cutting
costs for MRO and improving overall quality.
BKS, Beyond Expectation

14. 14
Questions
?
How can BKS help to control your costs for
MRO?

15. 15
Thank you for your
attention EadseSalesJong
Technical
de
Manager
BKS Pelletizing & Pulverizing
Technology
RUE JEAN KOCH 4
4800 LAMBERMONT
BELGIUM
EDEJONG@BKS.BE
WWW.BKS.BE