A new standard in refractory rollers, from Sirtec research and development
In roller kilns for the ceramic industry, roller quality is no minor detail: it determines firing consistency, equipment service life and the costs that build up when something goes wrong. Deformation, breakage, kiln downtime and visual defects in the finished product often share a common cause: a roller that cannot withstand the thermal and mechanical stresses it faces every day.
This understanding led to Siroll® HPR, the latest solution developed by Sirtec’s research and development department. More than a simple addition to the range, this roller was designed around a specific idea: using geometry to improve both roller stability and firing quality. The result is a product with a patented helical profile, a feature that clearly sets it apart from traditional cylindrical rollers.
What is Siroll® HPR?
Siroll® HPR is a dimensionally stable refractory roller for ceramic kilns, engineered using an LP80 base grade with a high modulus of elasticity. This combination of material and geometry brings together two qualities that make a real difference in service: excellent flexural strength and good stability under temperature changes.
Its most immediately striking feature, however, is its profile. Instead of a conventional cylindrical surface, HPR uses a helical design that moves air inside the kiln channel, makes firing more uniform and reduces the most costly problems: deformation, black core and kiln downtime.
Developed through dialogue with production teams
Like the entire Siroll® range, HPR was developed with practical experience at its core. It builds on ongoing research into optimising production processes and constant dialogue with end users. Real operating conditions, with their everyday challenges, guided the development of this new profile: a way to respond precisely to actual needs rather than theoretical specifications.
How the helical profile works
The helical profile is the technological heart of HPR and the basis for its patent. Its geometry works in two ways at the same time.
On the one hand, it reduces the contact area between roller and tile, limiting the marks and imperfections that continuous contact can leave on the product. On the other, it promotes air movement above and below the roller plane inside the firing channel. This more efficient circulation produces a more uniform temperature and improves firing efficiency throughout the tile’s journey.
Compared with a traditional cylindrical roller, this air movement, combined with the high modulus of elasticity of the LP80 base grade and its high flexural strength, makes HPR a more stable roller in service.
Why rollers deform (and how HPR prevents it)
It is useful to recall an often overlooked principle: a roller deforms when it stops rotating. Heat and load acting on a stationary roller bend it irreversibly. HPR tackles the problem on two levels. The LP80 base grade with its high modulus of elasticity provides excellent flexural strength, while the helical geometry distributes stresses more effectively. In all cases, it remains good practice to keep the roller rotating at all times, including during insertion and removal.
Where HPR is used in the kiln
HPR delivers the greatest benefits in kiln zones where its helical geometry directly influences the firing process.
Preheating zone
This is where improved tile degassing makes a difference: HPR helps eliminate black core and contributes to shorter firing cycles, delivering a direct productivity gain.
Transition from firing to rapid cooling
During this critical stage, the helical profile eliminates the “roller effect”, the shading that can appear on the fired product, improving its final appearance.
Throughout the firing channel
Air movement along the entire channel makes the temperature more uniform and reduces shade and calibre variations, one of the most frustrating problems for manufacturers seeking consistent quality.
Typical applications are those of the ceramic industry served by Sirtec: tiles, porcelain stoneware and large formats.
Features and benefits
Each HPR technical feature delivers a tangible process benefit that can be verified directly on the production line:
- LP80 base grade with a high modulus of elasticity – maximum flexural strength and dimensional stability.
- Patented helical profile – an exclusive design with no equivalent on the market.
- Improved degassing during preheating – less black core and shorter firing cycles.
- Elimination of the roller effect – no shading and improved product appearance.
- Reduced rings and build-up – easier maintenance and longer roller life.
- More uniform temperature along the channel – fewer shade and calibre defects.
A patented product, more than a marketing claim
One of the features that makes HPR unique is its protected intellectual property. This is a recognised, registered exclusive right, rather than a commercial promise:
- Utility Model No. 202022000003711 – the geometry of the helical-profile roller is patented.
- Registered Community Design No. 015019706-0001/0003 – the design is protected throughout the EU.
HPR is the only helical-profile roller in the Siroll® range, with no equivalent products offered by competitors. It is already well established: HPR helical rollers are used by the world’s leading manufacturers of kilns and ceramic tiles.
Sirtec’s data-driven approach
In keeping with the company’s approach, HPR performance is backed by more than words. Sirtec has its products tested by an independent ACCREDIA-accredited laboratory, in accordance with EN 993-1:2018 and ASTM E1876, with creep testing performed to ISO 3187:1989. This gives customers verifiable, comparable data rather than simple statements.
Why choose Siroll® HPR?
Choosing the right refractory roller means cutting the hidden costs of a roller kiln: deformation, breakage, kiln downtime and firing defects, all problems that prove expensive when they occur. Siroll® HPR meets this need by bringing together a high-performance material and innovative geometry in a single solution.
For manufacturers of tiles, porcelain stoneware and large formats, HPR is an investment that pays off through process continuity, the visual quality of the finished product and reduced kiln downtime. It demonstrates how applied research can turn a seemingly simple component into a real competitive advantage.
For full technical data and to assess HPR for your installation, the best approach is to speak directly with Sirtec’s technical support team, who can recommend the most suitable configuration for your kiln’s specific operating conditions.
