ELEMENTS OF PUMPS AND FITTINGS

n production and maintenance of abrasive medium transportation pimps in chemical industry, the most important task is to obtain on effective sealing to ensure the more reliable flow. Due to corrosion and rapid wear of metal, graphite or plastic sealing elements, the pumps had to be stopped frequently for replacement of these elements. With the occurrence of 99.7% Al2O3 sealing elements these pump problems were successfully eliminated. High abrasion and corrosion resistance of ceramic sealing elements enabled their usage with rotary and piston pumps, sanitary fittings, etc.- Sealing rings are made of 99.7% Al2O3 ceramics in various shapes and size, with maximum diameter up to 150 mm, depending on design and power of the pump.- After sintering, they are machined with diamond tools and polishing pastes so that the sealing face quality after polishing is as high as Ra=0,2 ?m.- Sealing cartridges on pump shafts provide good sealing and resistance to wear and chemical attack. Depending on pump parameters, i.e. shaft diameter, the cartridges may be produced in various diameters, lengths and shapes.- The external sealing face is polished to surface finish of Ra=0,2-0.8?m.- Pistons made of 95_99.7% Al2O3 ceramics have found an extensive application in piston pumps for chemical industry. Produced in several design variants, they perform their function perfectly for tens of thousands of working hours owing to high hardness, strength and abrasion resistance of ceramics. - Depending on power, pressure and capacity of the pump the pistons may have diameter of up to 125 mm and different lengths.- Cylindrical sealing face is polished to surface finish of Ra=0.2-0.6?m.