The influence of the conditions of gypsum plaster preparation on its technological properties
Journal Title: Archiwum Odlewnictwa - Year 2010, Vol 10, Issue 2
Abstract
The results of researches on influence of basic preparation parameters, i.e. time and mixing intensity, start and end time of set, dimensional changes and strength of gypsum plaster, are presented in this paper. Determination of mentioned above parameters has a significant meaning because of their influence on quality of gypsum plaster and its susceptibility to even small disturbances during preparation. Tested plaster was prepared in vacuum mixer St. LOUIS 82. Time of mixing was 60÷360 sec., mixer arm rates 150÷420 rpm. It was demonstrated that mixing time influences strongly the setting time and expansion of gypsum plaster , and this influence growths with growing mixing intensity. The intense, short time mixing is beneficial from the viewpoint of dimensional changes minimizing. Minimizing the setting time is the most beneficial at low mixing intensity but significant dimensional changes appear during setting the plaster.
Authors and Affiliations
M. Pawlak
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