TecnoClean CeraHybrid – Complete Dryer Cylinder Surface Solution

Grinding, high-performance coating and doctoring – engineered as one solution

The performance of a dryer cylinder depends on more than the coating alone.

Surface geometry, coating properties and the doctoring system all interact with each other and influence paper release, cylinder cleanliness, runnability, drying performance and the lifetime of the cylinder surface.

For this reason, PR Rolls approaches dryer cylinder optimisation as a complete surface solution rather than simply a coating application.

Our solution combines three essential elements:

Precision Grinding + TecnoClean CeraHybrid Coating + Optimised Doctoring Solution

By considering these elements together, PR Rolls can restore the cylinder geometry, create the required functional surface and ensure that the doctoring system works correctly with the new coating.

The result is a complete solution designed around the actual operating conditions of the paper or board machine.

More Than a Coating – A Complete Dryer Cylinder Solution

A high-performance coating cannot compensate for incorrect cylinder geometry.

Likewise, even an excellent coating can perform poorly if the doctor blade, blade material, holder or doctoring parameters are not suited to the coated surface.

PR Rolls therefore treats the dryer cylinder as a complete functional system.

Our approach addresses:

1. Cylinder Geometry – Grinding
The cylinder is inspected and, where necessary, precision ground to restore the required shape and surface condition.

2. Functional Surface – TecnoClean

CeraHybrid
A hard carbide base and nano-fluoride hybrid surface are applied to provide wear resistance, excellent release and resistance to contamination.

3. Surface Management – Doctoring Solution
The doctoring solution is selected and optimised to work with the coated surface, helping keep the cylinder clean while avoiding unnecessary wear.

Together, these three elements provide the foundation for long-term dryer cylinder performance.

What Problems Does the Complete Solution Address?

Dryer cylinder problems rarely have only one cause.

A contaminated cylinder, for example, may appear to be a coating problem. But the actual situation can involve a combination of:

• Incorrect cylinder geometry
• Surface wear
• Corrosion
• Poor paper release
• Sticky build-up
• Paper dust and fluff
• Incorrect doctor blade selection
• Excessive doctor blade pressure
• Uneven doctor loading
• Poor doctoring performance
• Damaged or worn doctor equipment

Simply applying a new coating may therefore leave the underlying problem unresolved.

PR Rolls evaluates the cylinder surface, geometry, coating requirements and doctoring conditions as one complete system.

Step 1 – Precision Dryer Cylinder Grinding
The foundation for a high-performance surface
The first step is to ensure that the dryer cylinder itself has the correct geometry and surface condition.

Over time, cylinders can develop:

• Wear
• Corrosion
• Scratches
• Scuff marks
• Surface contamination
• Geometry deviations
• Uneven previous coatings

Applying a high-performance coating over an incorrect surface does not correct these underlying problems.

Where required, PR Rolls therefore begins the project with precision on-site dryer cylinder grinding.

Grinding removes damaged and contaminated material while restoring the required cylinder geometry and creating the correct foundation for subsequent surface preparation and coating. This sequence is also specified in PR Rolls' current TecnoClean CeraHybrid process.

The objective is not simply to create a smooth surface. It is to establish the correct geometry and surface condition for the complete solution.

Step 2 – TecnoClean CeraHybrid Functional Coating
Excellent release combined with wear resistance
Once the cylinder geometry and substrate have been correctly prepared, the functional surface can be created.

TecnoClean CeraHybrid is a carbide and nano-fluoride composite coating developed for demanding paper and board machine dryer cylinder applications.

The coating combines two important functions.

Hard Carbide Base
The base coating provides:

• High hardness
• Wear resistance
• Protection of the underlying cylinder
• Long-term mechanical durability
• Nano-Fluoride Hybrid Surface

The functional hybrid surface provides:

• Excellent paper release
• Low adhesion
• Resistance to sticky build-up
• Reduced dust and fluff accumulation
• Easier doctoring
• Cleaner cylinder operation

The carbide base is applied using HVOF or HVAF thermal spraying before the functional hybrid coating is applied.

Together, the layers create a durable functional surface – but the coating remains one part of the complete PR Rolls solution.

Step 3 – Doctoring Solution
Matching the doctoring system to the coated cylinder
Doctoring is a critical part of dryer cylinder surface performance.

The doctor must keep the cylinder clean, but excessive or incorrectly distributed blade pressure can increase friction, energy consumption and wear of both the blade and coated surface.

For this reason, the doctoring solution should be considered together with the grinding and coating specification.

PR Rolls' approach is to ensure that the doctoring conditions are compatible with the functional cylinder surface.

Depending on the application, the doctoring solution can consider factors such as:

• Doctor blade material
• Blade type
• Blade loading
• Contact pressure
• Pressure distribution
• Doctor holder condition
• Doctor geometry
• Profiling
• Maintenance requirements

The objective is controlled and efficient doctoring that keeps the TecnoClean CeraHybrid surface clean without unnecessary mechanical loading.

This approach is supported by PR Rolls' practical experience. In the Lenk Paper MG cylinder project, PR Rolls' surface work was combined with modifications to the doctoring systems, blade-holder adjustment and measurement of line-load distribution to ensure the new coated surface could be doctored correctly.

Why Coating and Doctoring Must Work Together

A coating and doctor blade are in continuous interaction during production.

Changing the surface properties of the cylinder without considering the doctoring conditions can therefore lead to an incomplete solution.

The combination must achieve two objectives:

The coating should resist contamination and release paper efficiently.

The doctoring system should keep the surface clean without unnecessarily wearing the coating.

TecnoClean CeraHybrid is specifically designed to be easy and light to doctor. PR Rolls reports that this can reduce energy use and extend doctor blade operating life.

Optimising the complete system can therefore support:

• Cleaner cylinder surfaces
• Reduced doctoring pressure
• Reduced friction
• Longer doctor blade life
• Reduced coating wear
• More stable surface conditions
• Longer maintenance intervals

Where is the TecnoClean CeraHybrid Solution Used?

The complete grinding + coating + doctoring solution is designed for demanding dryer cylinder positions where surface condition directly affects paper release and machine performance.

TecnoClean CeraHybrid is particularly suited for:

Cylinders at the Beginning of the Dryer Section
At the beginning of the dryer section, reliable sheet release is particularly important.

A correctly ground cylinder with an appropriate functional coating and optimised doctoring can provide a cleaner and more consistent surface for this demanding machine position.

Cylinders After the Sizer
Sizing can create additional contamination and adhesion challenges.

The TecnoClean CeraHybrid surface helps resist build-up while the doctoring solution keeps the functional surface clean during operation.

Cylinders After the Coating Station
Coating residues and other process contaminants can make downstream dryer cylinders especially demanding.

TecnoClean CeraHybrid is designed for these applications where excellent release and resistance to contamination are required. PR Rolls specifically identifies cylinders at the beginning of the dryer section and those following sizer and coating stations as core applications.

Improve Paper Release and Reduce Draw

One of the main objectives of the TecnoClean CeraHybrid solution is improved paper release.

When paper adheres too strongly to a dryer cylinder, additional draw may be required to separate the sheet from the surface.

The functional TecnoClean CeraHybrid surface reduces adhesion and helps the paper release more easily.

PR Rolls associates this improved release with:

• Reduced need for draw
• Better runnability
• Reduced dust generation
• Improved paper quality
• Improved paper profile

But maintaining these characteristics over time also requires the surface to remain clean.

This is why coating performance and doctoring performance should be considered together.

Reduce Sticky Build-up, Dust and Contamination

Depending on the machine position and produced grade, dryer cylinders can be exposed to:

• Paper dust
• Fibres
• Fluff
• Sticky contaminants
• Sizing residues
• Coating residues
• Other process deposits

TecnoClean CeraHybrid creates a low-adhesion surface designed to resist this build-up.

The doctoring solution complements the coating by removing contaminants that do reach the cylinder.

Instead of relying on aggressive doctoring to compensate for a surface that attracts contamination, the objective is to create a surface and doctoring combination that works efficiently together.

Cleaner Cylinders for Efficient Drying

A dryer cylinder must transfer heat efficiently to the paper web.

Contamination and deposits on the cylinder can create an unwanted layer on the heat-transfer surface.

Maintaining a clean cylinder is therefore important for both runnability and drying performance.

TecnoClean CeraHybrid is designed to remain clean and conduct heat effectively. PR Rolls associates these characteristics with increased drying capacity and more efficient energy use.

The complete solution supports this by combining:

Correct geometry → Functional coating → Effective surface cleaning

A System Approach to Dryer Cylinder Performance

PR Rolls does not view grinding, coating and doctoring as three unrelated maintenance operations.

They influence each other.

A simplified way of understanding the relationship is:

Grinding
restores the underlying cylinder geometry and creates the correct foundation.

↓

TecnoClean CeraHybrid coating
creates the functional surface characteristics required for release, wear resistance and cleanliness.

↓

Doctoring solution
maintains the functional surface during production.

↓

Complete cylinder performance
supports release, cleanliness, runnability, drying and long-term surface condition.

This system approach is an important difference between buying a coating and investing in a complete dryer cylinder surface solution.

On-site Grinding and Coating

Another important advantage of the PR Rolls solution is that the grinding and coating can be performed directly in the paper machine.

Large dryer cylinders do not necessarily need to be removed and transported to an external workshop.

PR Rolls' on-site dryer cylinder service is specifically designed around grinding and coating cylinders in the machine, including the possibility of working on several cylinders during the same shutdown.

Benefits include:

• Reduced dismantling
• No unnecessary cylinder transportation
• Less heavy lifting
• Several cylinders can be serviced during the same shutdown
• Grinding and coating can be coordinated as one project
• Doctoring requirements can be considered as part of the solution
• Shorter maintenance lead times
• Faster return to production

The Complete PR Rolls Delivery

Depending on the condition of the machine and project requirements, a TecnoClean CeraHybrid project can include:

1. Condition Assessment
Evaluation of the cylinder surface, geometry and operating problems.

2. Precision Measurement
Measurement of the cylinder condition and geometry where required.

3. On-site Grinding
Restoration of the cylinder geometry and removal of wear, corrosion and surface defects.

4. Surface Preparation
Preparation of the restored substrate for thermal spraying.

5. Carbide Base Coating
Application of the hard, wear-resistant carbide layer using HVOF or HVAF.

6. TecnoClean CeraHybrid Functional Surface
Application of the nano-fluoride hybrid layer to create the required release and non-stick properties.

7. Surface Finishing and Verification
Inspection and finishing of the coated surface.

8. Doctoring Solution
Selection, adjustment or optimisation of the doctoring system to match the new functional surface.

9. Final Verification
Verification of the complete surface solution and, where required, additional services such as balancing.

The exact scope is adapted to the condition and requirements of the individual machine.

Why Choose a Complete Solution Instead of Coating Alone?

A coating supplier primarily addresses the surface material.

PR Rolls' approach is broader.

We look at the complete interaction between:

Cylinder geometry + Surface properties + Doctoring

This provides several advantages.

One coordinated solution
Grinding, coating and doctoring requirements can be planned together instead of treating them as separate projects.

Correct foundation for the coating
Precision grinding ensures that the coating is applied to a correctly restored cylinder surface.

Doctoring matched to the coating
The doctoring solution can be selected and optimised according to the characteristics of the functional surface.

Reduced risk of treating symptoms instead of causes
Surface contamination, poor release and excessive doctoring may have several interacting causes. Evaluating the complete system helps identify the appropriate solution.

Lifecycle perspective
The objective is not simply to apply a new coating during the shutdown, but to achieve reliable surface performance throughout the operating period.

TecnoClean CeraHybrid Technical Properties

TecnoClean CeraHybrid forms the functional coating element of the complete PR Rolls dryer cylinder solution.

These specifications correspond to PR Rolls' current published technical data.

When Should You Consider the TecnoClean CeraHybrid Solution?

A complete surface solution should be considered when dryer cylinder problems cannot be addressed reliably through cleaning or coating alone.

Typical indicators include:

• Poor paper release
• Excessive draw
• Sticky build-up
• Frequent cylinder cleaning
• Paper dust and fluff
• Uneven or worn cylinder surfaces
• Corrosion
• Excessive doctor blade wear
• High doctoring pressure
• Unsatisfactory doctoring performance
• Repeated coating problems
• Runnability problems associated with cylinder surfaces
• Problems after sizing or coating stations

Rather than selecting a coating first, PR Rolls can evaluate the operating problem and determine the appropriate combination of grinding, coating and doctoring.

Why Choose PR Rolls?

PR Rolls combines capabilities that are often treated as separate disciplines.

Our expertise includes:

• Dryer cylinder condition assessment
• Precision measurement
• On-site cylinder grinding
• Surface restoration
• HVOF/HVAF thermal spraying
• Functional coating technology
• TecnoClean CeraHybrid
• Doctoring solutions
• Surface finishing
• Field balancing
• Dryer section optimisation

This allows PR Rolls to focus on the performance of the complete cylinder system rather than the coating in isolation.

PR Rolls' broader dryer cylinder offering already combines on-site grinding and coating, while its published reference projects demonstrate how surface restoration can be integrated with doctoring-system modifications.

Frequently Asked Questions

Is TecnoClean CeraHybrid only a coating?
TecnoClean CeraHybrid is the functional coating technology, but PR Rolls can deliver the solution as a complete package combining dryer cylinder grinding, TecnoClean CeraHybrid coating and a doctoring solution. The objective is to optimise the complete cylinder surface system rather than treating coating as an isolated maintenance operation.

Why should the cylinder be ground before coating?
Grinding removes wear, corrosion, dirt and surface damage while restoring the correct cylinder geometry. This creates the required foundation for the subsequent coating process.

Why is doctoring included in the solution?
The doctor blade continuously interacts with the coated surface. Blade material, loading and pressure distribution therefore influence cleanliness, friction, coating wear and doctor blade lifetime. Matching the doctoring solution to the coated surface supports long-term performance.

What is TecnoClean CeraHybrid?
TecnoClen CeraHybrid is a carbide and nano-fluoride composite coating developed for paper and board machine dryer cylinders. The carbide base provides wear resistance while the functional hybrid surface provides excellent release and resistance to contamination.

Where is TecnoClean CeraHybrid used?
The coating is particularly suited for cylinders at the beginning of the dryer section and cylinders following sizing and coating stations.

Can grinding and coating be performed on-site?
Yes. PR Rolls specialises in grinding and coating dryer cylinders directly in the paper machine, reducing the need for cylinder removal and transportation.

Can PR Rolls optimise the doctoring system for a coated surface?
PR Rolls' reference work demonstrates that coating projects can include doctoring-system modifications, blade-holder adjustment and line-load evaluation to achieve appropriate doctoring of the new surface.

What are the main benefits of the complete solution?
The objective is to achieve the right cylinder geometry, functional surface and doctoring conditions together. This can support cleaner cylinders, easier paper release, reduced draw, efficient doctoring, improved runnability and longer surface life.

One Solution for the Complete Dryer Cylinder Surface

A high-performance dryer cylinder requires more than a high-performance coating.

The geometry underneath the coating must be correct. The functional surface must suit the process. And the doctoring system must work correctly with that surface.

PR Rolls therefore delivers TecnoClean CeraHybrid as part of a complete dryer cylinder solution:

Precision Grinding + TecnoClean CeraHybrid Coating + Doctoring Solution

By bringing these elements together, PR Rolls helps paper and board producers address the complete surface system – from restoring cylinder geometry to creating the functional coating and maintaining that surface during production.