Consistent high quality is guaranteed by the correct mixture of the natural raw materials clay, grog and water and high-tech manufacturing processes developed over many years. Every single process step is monitored by a sophisticated quality management system.

VITRIFIED CLAY – THE MATERIAL

FOREVER DOWN-TO-EARTH

Processing

Clay and grog are carefully ground, then mixed with water and homogenised.

Forming

Pipes are formed using vacuum extruders that shorten drying and firing times.

Drying

Pipes dry at about 80 °C. Modern production technology like rapid drying allows drying time to be reduced and tolerances to be minimised.

Some manufacturers glaze products, dipping pipes and fittings either before or after drying in a glazing liquid made of clay, lime, dolomite, quartz, metal oxides and water.

Firing and vitrification

Firing (at temperatures of about 1250°C) is the most important process; it is during kiln firing that vitrification – heat fusion – occurs. It is here where absolute perfection is required: products leaving the kiln have to be perfectly accurate.

Jointing

After firing, socket/spigot pipes are jointed with systems in accordance with EN 295; plain ended pipes may have couplings factory fitted or couplings may be supplied loose.