Fire-resistant ordinary ceramic batch, and fire-resistant product therefrom

A refractory product in the form of a pressed large shaped body which has been heat treated at temperatures in the range from 80 to 800° C., produced from a batch (mix) comprising:

• a) at least one granular, refractory, mineral basic main component comprising one of an MgO- and an MgO and CaO-based refractory material and
• b) at least one granular, refractory, mineral, MgO-based, spinel-free elasticizing additive in a form selected from a group consisting of:
• b1) a forsterite material additive having the following particle size distribution:
• 1-6 mm:
• from 50 to 100% by weight, in particular from 70 to 80% by weight 0.25-1 mm:
• from 0 to 50% by weight, in particular from 20 to 30% by weight;
• and
• b2) a granular component additive composed of small shaped bodies which as ground powder mixtures comprise only the forsterite materials for in-situ formation of said forsterite material and have a particle size of from 0.3 to 8 mm, whereby the small shaped bodies are a mixture of ground powders of at least one MgO- and at least one SiO2-component;
• whereby the additive being present in the batch (mix) in an amount which elasticizes the main component;
• and
• wherein the main component is present with the following particle size distribution, preferably in combination with the additive in a particle size distribution of a typical Fuller curve:
• 1-8 mm:
• from 20 to 50% by weight, in particular from 45 to 50% by weight,
• 0.25-1 mm:
• from 10 to 30% by weight, in particular from 15 to 20% by weight,
• <0.25 mm:
• from 20 to 60% by weight, in particular from 25 to 30% by weight.

A coarse-ceramic refractory batch (mix) comprising:

• a) at least one granular, refractory, mineral basic main component comprising one of an MgO- and a MgO and CaO-based refractory and
• b) at least one granular, refractory, mineral, MgO-based, spinel-free elasticizing additive in a form selected from a group consisting of
• b1) a forsterite material additive having the following particle size distribution:
• 1-6 mm:
• from 50 to 100% by weight, in particular from 70 to 80% by weight 0.25-1 mm:
• from 0 to 50% by weight, in particular from 20 to 30% by weight;
• and
• b2) a granular component additive composed of small shaped bodies which as ground powder mixtures comprise only the forsterite materials for in-situ formation of said forsterite material and have a particle size of from 0.3 to 8 mm, whereby the small shaped bodies are a mixture of ground powders of at least one MgO- and at least one SiO2-component;
• whereby the additive being present in the batch (mix) in an amount which elasticizes the main component;
• and
• wherein the additive forsterite material has included periclase grains having, in particular, grain sizes in the range from 30 to 900 μm, preferably from 50 to 200 μm, dispersed in the forsterite material in amounts of, in particular, up to 25% by weight, preferably from 3 to 15% by weight.