Improved strength and surface properties

Valmet sizers for board and paper machines

Valmet’s sizer product family offers all application methods and all paper machine sizes available - spray, film and pond application and a new types of a sizer with hard nip rolls and curtain sizing. All sizers have a robust and modular construction combined with high functionality and quality with a low total cost of ownership. In surface sizing or size application, starch, or other types of size or pigmented size, is applied to the paper web surface to improve its strength, surface properties or water resistance. Sizing is often used to modify surface properties before coating.

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Get to know our OptiSizer product family. Click on the link below to read and find out more on our sizing solutions.

Valmet’s sizers feature smart construction

You can rely on Valmet's sizing solutions, which are proven and safe. The sizers have excellent reliability; they need less maintenance and there are less unexpected shutdowns.

When you are purchasing a new sizer, the scope of delivery will be clear and the solution will be flexible for auxiliary or optional choices. The design is done for easy upgrades when needed.

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Learn more about our OptiSizer solutions

OptiSizer Film sizing

OptiSizer Film offers a functional and innovative design, based on know-how and long experience. Its simple and reliable design results in easy operation, installation and fast initial start-up.

OptiSizer Hard sizing

OptiSizer Hard is uses higher nip loads to improve sheet strength properties by taking advantage of better starch penetration and decreasing fiber to fiber distance.

OptiSizer Curtain sizing

The new surface sizing method applies the starch as a curtain of size. When combined with hard-covered rolls the results with coated cartonboards are significant: stiffness, quality and production increased, and energy and raw material consumption reduced.

OptiSizer Spray sizing

In surface sizing, the size is sprayed on nip rolls through a row of spraying nozzles. Then, the size is transferred to the web in the nip. You can control the amount of size accurately and fast, and there are no consumables due to contactless application, which leads into decreased downtime.

OptiSizer Combi sizing

OptiSizer Combi combines different size application methods in one process to benefits of both technologies when paper top and bottom sides have completely different needs.

OptiSizer Pond sizing

Pond size application technology is primarily designed for specialty paper grades, heavy printing papers, and for board when through-sizing is needed.

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Building the future of packaging with cutting-edge technologies in Kıvanç Paper PM 1

Mar 4, 2026

Discover how Kıvanç Paper decided to take a major strategic leap by entering the board manufacturing industry. At the core of this greenfield mill investment are Valmet’s innovative technologies, many of which have never been seen anywhere in the world before. The board making line delivery included an OCC line, stock preparation and white water treatment, board machine PM 1 from headbox to reel and winder, and services and automation for the entire mill.

OptiSizer Hard: Improved strength with hard nip sizing

Aug 26, 2025

Innovative OptiSizer Hard uses high nip loads to improve sheet strength properties by taking advantage of the better starch penetration in the base sheet. The deflection compensated rolls with hard covers give high loading capacity and good profile features resulting in excellent runnability.

Pilot trials on finishing technology at Valmet Paper Technology Center in Järvenpää

Feb 25, 2025

Experience our Paper Technology Center in Järvenpää, Finland, where you can pilot and test latest finishing technologies. The pilot facility offers extensive pilot trials on finishing technology, covering all grades and different finishing technologies from sizing to reeling, winding, and runnability testing.

Successful market expansion through grade conversion rebuild – Cascades Containerboard Packaging – Bear Island

Dec 10, 2024

Video: Valmet was chosen as the selected partner by Cascades for their strategic market expansion project in southeastern U.S. They acquired an old newsprint machine that was converted to produce lightweight, high-quality, 100% recycled linerboard and corrugating medium for the North American market.

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Kıvanç Paper PM 1: Building the responsible future of packaging with cutting-edge technologies

Mar 4, 2026

Backed by decades of expertise in the textile industry, Kıvanç Paper decided to take a major strategic leap by entering the board manufacturing industry, with the goal of contributing to the local economy and sustainable board production. At the core of this greenfield mill investment are Valmet’s innovative technologies, many of which have never been seen anywhere in the world before.

Practical collaboration and efficient production for high quality

Apr 22, 2025

Shandong Bohui Paper’s huge new flagship papermaking line PM 8 produces premium-quality product with new levels of efficiency. Valmet delivered the entire papermaking line, including all automation and flow control solutions.

We’ve got you covered!

Mar 25, 2025

Papier- und Kartonfabrik Varel equipped all their sizer rolls with Valmet Sizer Roll Cover CF covers and the results are outstanding – the lifespan of the covers was extended to over six months, improving the production availability significantly.

Successful market expansion through grade conversion rebuild – Cascades Containerboard Packaging – Bear Island

Dec 10, 2024

Article: Cascades selected Valmet as their partner for a strategic market expansion project in southeastern U.S. An old newsprint machine was acquired and converted to produce lightweight, high-quality, 100% recycled linerboard and corrugating medium for the North American market.

MM Količevo BM 3: Investing for the future with OptiSizer Curtain

Oct 7, 2024

MM Board & Paper’s collaboration with Valmet reached a milestone in October 2023 when their rebuilt BM 3 board machine and the first-ever hard nip sizer with a curtain application were successfully started up at the MM Količevo mill in Slovenia.

Liansheng Pulp and Paper: big success with PM 1 carton board and PM 3 high-grade fine paper lines

Feb 27, 2024

Living up to expectations, Liansheng’s PM 1 carton board and PM 3 high-grade fine paper production lines have been recognized as a success not only by Liansheng, but also by their customers.

Guangdong Shanying: dedicated to intelligent, low-carbon manufacturing

Dec 13, 2023

With their new PM 52 and PM 53 lines, Guangdong Shanying aims to meet their low-carbon goals while setting industry benchmarks for intelligent manufacturing. Close cooperation with Valmet has enabled rapid start-up and exceptional efficiency.

Elevating containerboard manufacturing in India

Dec 13, 2023

Sri Andal is aiming at producing high-quality containerboard with tangible efficiency improvements and Valmet offers a suitable solution for achieving these targets.

How do you plan a successful rebuild?

Rebuilding a paper or board machine can improve the competitiveness of your business and your processes. Download our e-book to learn more.

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Get in touch with our pilot trial experts to discuss how you could benefit from our pilot trial services.

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Learn more about the services and automation solutions for sizing

Sizer consumables

Sizer consumables play an important role in film sizing and coating. When you choose products that are optimized for your machine and process, you chieve outstanding paper quality, maximized production capacity and a stable process. Our consumables have excellent wear resistance – meaning less downtime and fewer consumables used, and, thus more production and lower costs. 

Sizer roll covers

The film sizing and film coating process plays a critical role in determining both the strength and appearance of paper and board. As these processes are performed inline on the paper machine, they have a direct impact on machine efficiency, runnability, and final product quality. This places exceptionally high demands on sizer roll covers used in board and paper making.

Workshop and roll services for board and paper making

Valmet Workshop and Roll Services offer a winning combination of the latest roll technology and maintenance expertise. We help you eliminate unplanned shutdowns, increase the running times of rolls, improve the end product quality and lower the roll maintenance costs in long-term.

iRoll technology

Valmet iRoll technology improves production efficiency and product quality by assuring optimal runnability of board and paper machines. Papermaker can obtain significant cost savings by improved nip profiles, parent roll hardness profiles and tension profiles as well as printer and converter satisfaction.

Tail threading

A reliable tail threading process decreases tail threading times, minimizes waste and improves safety. This means an investment in your process is an investment that pays for itself. Whether you need improvements in paper or board machines, we have an advanced tail threading solution that clearly enhances your production efficiency. Our comprehensive range of tail threading services, from preventive maintenance to tail threading study secures optimal operation of your equipment and reduces threa...

Automation for Board and Paper

Valmet provides future-proof automation solutions for board and paper production. The industry-leading distributed control system (DCS), quality control system (QCS), analyzers and measurements continuously improve your process performance while achieving savings in fibers, chemicals, and energy.

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