Unshaped Refractories drying

Initially, when unshaped refractories were first used, the property requirement was kept the same as for shaped refractories, in thatthey mainly replaced linings. Later on, when the use of these refractories became widespread, new standards had to be developed. The first standards on unshaped refractories by the American Society for Testing of Metals (ASTM) were published in 1943 [3]. They were numbered as C 179 and C 181 C 179 covered "drying and firing linear change of plastics and rammings" and C 181 dealt with "workability index of plastic refractories." As noted earlier. World War II saw an increase of about 35% in unshaped refractory production. Specifications were required to obtain the required items from many manufacturers. 

Drying and heating up are started once the setting of the unshaped refractory is over. If fhese processes are started after long periods, then the following rules should be observed ... 

More than a third of all unshaped refractories will be installed by gunning. In a previous chapter the type of gunning was described Table 10 makes a comparison between the old traditional dry gunning technique and the shotcreting... 

Consequently, drying and heat-up should start immediately respectively 48 hours after the last concrete work However, it should be taken into consideration that a refractory lining made of unshaped refractories has much more residual water than a brickwork. 

Typically, the refractory layer is made from alumina silicate (most frequently fireclay) bricks or unshaped dry barrier mixtures. The main purpose of the... 

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