Page 136 - Gillrath Edition IV - EN
P. 136
PRODUCTION PROCESS
EXTRUSION VS. MOULDING
Extruded clinkers
Our classic product is the extruded clinker.
The extrusion press produces a continuous, smooth and perfectly moulded slab of clay. After the end- less clay strand is pressed through the respective mouthpiece at the extruder, the strand rolls on roll- ers until it reaches the cutter.
Individual units cut from the slab with wire are called ‘slugs’.
At this stage the slugs are larger than they will be as fired bricks. Shrinkage occurs as a result of water loss during the artificial drying and firing processes.
A finished clinker surface can
be smooth, sanded or hand- moulded to meet the customer’s wishes. By varying the type of clay in the raw mixture differ- ent colours can be produced.
Similarly, spectacular surface finishes can be achieved with the addition of salt or coal in the firing process or through the ‘smoking’ process.
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