SETTING ACCELERATORS Short setting times are required to keep lining and repair times of aggregates as short as possible. The use of a setting accelerator in cement-containing bodies allows the creation of a lattice of hardly soluble silicate compounds. This gives the components sufficient strength, and the result is that they can be removed from the moulds easily, before the cement bond develops its full potential.
Short setting times are required to keep lining and repair times of aggregates as short as possible. The use of a setting accelerator in cement-containing bodies allows the creation of a lattice of hardly soluble silicate compounds. This gives the components sufficient strength, and the result is that they can be removed from the moulds easily, before the cement bond develops its full potential.
Chemical binders are applied in refractory bodies to reduce or even replace hydraulic binding agents. These alternative binders allow a compaction of refractory gunning mixes. After drying, these gunning mixes can be heated faster than hydraulically bonded bodies.
Powder wetting agents permit – after their activation through water addition – the dispersion of hydrophobic raw materials in refractory gunning mixes (e.g. soot and graphite). Wetting agents are surface-active preparations exhibiting high surface affinity, which in turn decreases the surface tension of the preparation water.
The use of splinter porosity-inducing agents serves to adjust the pore size, pore volume and pore distribution in a targeted manner. A typical example of application is the manufacture of abrasive tools. Fibrous porosity-inducing agents are employed to reduce cracks and shrinkage and to permit faster de-watering.
In order to reduce dust formation when dealing with dry delivered gunning mixes, a dust binder is already incorporated into the body during the mixing process. This application is possible in bodies with ceramic, chemical and hydraulic bonding. Contrary to the customary dust binders, a good wetting is given during processing of the gunning mix.
