Research On The Formula Be Used As Casting Of The Flue Gas Desulfurization(FGD)Gypsum

Plaster mould precision casting is widely used because of it can forming highdimensional accuracy, surface roughness small profiled thin-walled parts, butcurrently the vast majority of using the natural gypsum. The flue gas desulfurizationgypsum as raw materials for the plaster mould precision casting gypsum, which canrealize power plant desulfurization gypsum waste recycling. In this paper, through theanalysis summary the formula of plaster mould precision casting both at home andabroad in recent years，research has been obtained the gypsum mold formula based onthe flue gas desulfurization gypsum as the raw material.The experimental results of the best ratio of the nature α-hemihydrate gypsumand the FGD β-hemihydrate gypsum was40:60in the flue gas desulfurization gypsummould, it could desirable the performance complementarities between the two kindsof hemihydrate gypsum.Using CAMTC-PMM1000-5X gypsum type digital processing and formingmachine for the desulfurization gypsum mould digital processing and forming, theexperiment obtained the forming process and cutting parameters of desulfurizationgypsum mould, the gypsum mould surface dimension precision was±0.300mm andverify the desulfurization gypsum used in the feasibility of the plaster mould precisioncasting.In this paper，we studied the formula based on the flue gas desulfurizationgypsum as the raw material, its composition was: natural α-hemihydrate gypsum22%, FGD β-hemihydrate gypsum33%, quartz powder20%, high bauxite25%andglass fiber0.3%, water reducing agent0.5%-0.7%, retarder0.03%-0.04%, deformingagent0.4%-0.5%. The room temperature and high temperature strength， lineshrinkage performance of the plaster mold was optimal, can satisfy the requirementsof the use of the casting.The drying and calcination technology that suitable for the desulfurizationgypsum mould was worked out，and successfully developed a certain military electricchassis and hull engine connecting rod casting，such as automobile manufacturing,machinery processing，and shipping areas the successful development and application.