Justification of rational parameters for manufacturing pump housings made of fibroconcrete

Abstract

Purpose. Establishment of patterns of influence of the main factors on the physicomechanical characteristics of fiber concrete, which is advisable to use for the manufacture of pump housings operating in adverse conditions.Methodology. The work uses theoretical analysis of fiber concrete application in various industries, analysis of factors affecting fiber concrete strength; laboratory experiments are conducted to confirm theoretical results and identify regularities allowing rec ommending rational parameters of production of pump casings from fiber concrete.findings. The work attempts to offer technological solutions for the use of fiber concrete in a new field -mechanical engineer ing -in the manufacture of pump housings operating in the mining and metallurgical industry in unfavorable conditions such as pumping of aggressive liquids, highly abrasive pulp, high ambient temperature, dust, and others. The obtained results allow devel oping centrifugal pump housing casting technology without additional mechanical treatment and with high physical and me chanical characteristics as well as recommending rational composition of the fiber concrete mixture, meeting requirements to centrifugal pump housings according to strength conditions, manufacturability and economy.originality. The regularities of the effect on the strength of fiber concrete of the optimal content of steel fiber in the composi tion of the mixture as well as rational modes of mixing components are established experimentally. They are rotational speed of a mixer working part and mixing time of the components. The obtained regularities confirm theoretical studies and provide obtain ing of the fiber concrete mixture with uniform distribution of all components in its volume as well as isotropic characteristics of solidified fiber concrete.Practical value. The obtained results, presented in graphs and calculation formulas, make it possible to reasonably design com position of the fiber concrete mixture and to develop the technology of making centrifugal pump housings from it by a casting method without additional mechanical treatment. At the same time fiber concrete has density of 2200-2300 kg/m 3 versus 7500-7800 kg/m 3 of metal bodies, compression strength of 230-240 MPa, bending strength of 80-100 MPa. All these allow reducing thickness of a pump housing wall by 15-20 %.

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