Definitions, Classifications, and Standardization

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. 

There was no uniform standard in Europe until the 1960s. In 1953, the Federation Europeenne des Fabricants de Produit Refractaires (PRE) was established to provide technical recommendations. To avoid any divergence of ideas between the refractories manufacturers belonging to PRE and the refractory users, mixed groups were set up in 1969 under the name Siderurgie et PRE (SIPRE). In February 1964, PRE Bulletin No. 65 was published, which contained 

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Definitions, classifications and standardization of services Until now there has been only a diffuse understan ng of the topic of service. In particular, international definitions, classifications, and standmds, which are necessary in order to develop, bundle, and trade services in the future in the same way as material products, are currently not available. Research questions to be solved include which structural elements of services can be identified, how they should be considered in the development, and how they can be made operational, as well as which methods and instruments could be used for the description and communication of internal and external services. 

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