In 2026, Insulcon marks 30 years since the introduction of the Refrex® Expanchor® Lining System, REL®. What started as a practical solution to fibre erosion and product contamination in a sanitaryware kiln has developed into a proven system used in a wide range of high temperature industries.
The development of REL® started at Sphinx Sanitair in Maastricht, the Netherlands. In 1992, an initial trial was carried out using Refrex® 1420 fabric over an existing fibre lining in a Coeltunnel kiln.
The trial demonstrated that a heat resistant fabric could protect the underlying low thermal mass fibre lining. However, the fastening method used at the time was not yet suitable for large scale application. Perforating the steel kiln structure was not considered an acceptable solution by the customer.
In May 1996, the first Expanchor® prototype was therefore introduced. This made it possible to securely install Refrex® fabric over an existing fibre lining without completely replacing the original fibre lining. In the years that followed, additional sections of the kiln at Sphinx were gradually equipped with REL® 1420.
Low thermal mass fibre linings offer important advantages, including low weight, rapid heat up and good resistance to thermal shock. After prolonged operation, however, shrinkage gaps and erosion may occur, potentially resulting in hot spots and loose fibre particles.
REL® combines flexible Refrex® ceramic fabric with ceramic Expanchors®. The fabric forms a protective hot face, the process exposed inner surface of the fibre lining, and helps limit further erosion and product contamination.
The system was initially developed for sanitaryware and ceramic kilns, where loose fibre particles can directly affect the quality of glazed products. Historical technical documentation also describes benefits such as covering shrinkage gaps, increased resistance to gas flow and a more durable hot face finish.
Following its first applications in sanitaryware ceramics, REL® was further developed for use in a wide range of industrial kilns and furnaces.
• Ceramics and porcelain
• Glass
• Secondary steel processing and heat treatment
• Secondary aluminium processing
• Petrochemical industry
• Chemical process industry
Documented references include Duravit, Meissen Porzellan, Schott Glass, Bosch, BP Gelsenkirchen, Dow Terneuzen, FIB Belgium and Aleris. The reference list includes projects throughout Europe and beyond.
Not every existing fibre lining needs to be completely replaced. When a module or stackbond fibre lining is still thermally and structurally suitable for continued use, REL® can be applied as an upgrade and protective hot face.
When the existing fibre lining requires complete replacement, Refrex® New Lining, RNL®, may be the more suitable solution. In this case, a new layered low thermal mass fibre lining is constructed with Refrex® forming the protective hot face.
The correct solution depends on several factors, including:
• The condition of the existing fibre lining
• Operating temperature
• Furnace atmosphere
• Gas flow
• Mechanical load
The basic principle of REL® has remained unchanged for thirty years: providing a practical way to improve the protection of existing fibre linings. At the same time, materials, fastening methods and application possibilities have continued to develop.
Current Refrex® grades are available for continuous operating temperatures up to 1200°C and 1300°C. The current Expanchor® ET versions are mechanically connected to the steel casing and are suitable for refurbishment, repair and customised fibre lining configurations.
Every application is different. Insulcon therefore assesses each kiln or furnace individually to determine the most suitable system configuration.
Visit the updated product page for more information about how REL® works, product selection, applications and the difference between REL® and RNL®.
A complete REL® and RNL® reference list is available on request
