MANUFACTURING PROCESS AND TECHNOLOGICAL
FORGESTAL MEANS INNOVATION IN EXTRUSION
All refractory parts are manufactured by the plastic shaping process, either by plain extrusion or by extrusion plus re-pressing, of the mixes composed of refractory chamotte, refractory clays and additives.
Different refractory chamottes combined with the right proportions of own refractory clays and additives produce a wide range of mixes with varying degrees of thermal shock resistance and refractoriness up to 1400ºC operating temperature.
Some of the main technological advantages of this process, as performed by Campo/Forgestal, against dry pressing are:
Total flexibility of shapes, including tridimensional and hollow ones, is an excellent basis for innovative designs. Hollow shapes allow for:
Lighter linings resulting in lower energy consumption.
Faster heating up and cooling down of the refractory parts in contact with the ceramic ware, resulting in a reduced
energy consumption, a better quality of the fired ware and, quite often, a shortening of the firing cycle and therefore in a higher output. It is well known that a higher output means an additional energy saving per unit of fired ware because the losses through walls and roof remain constant.
Compactness and strength are not affected by differences in thickness, the forming process being highly isostatic becau
se of the flowing capacity of the plastic body.
Lower and smaller size porosity is an efficient strategy against chemical attack penetration. This feature is especially relevant when alkali containing clays and/or aggressive fuels are used.
Thermal shock resistance, based on a high percentage of cordierite together with a very low percent of free quartz, is enhanced by the “sponge like” network of the high cordierite matrix surrounding the chamotte grains.
A high dimensional accuracy is achieved by means of a strict control of the mixing and manufacturing parameters, completed by the diamond cutting at exact length of all parts.
Additionally, grinding facilities are used when an extreme precision and/or flatness is required, as it is the case for the big size setting supports or the supporting parts for U-cassettes or H-cassettes.