Repair of the shaft coupling for multi-stage centrifuges in York Industrial cryogenic propylene units M326A8 and M425B3

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Maintenance and analysis of shaft seizure in multi-stage centrifuges of York Industrial refrigeration propylene units such as M326A8 and M425B3: 1. Lack of oil: The oil film inside the compressor is thin or absent, resulting in a loss of lubrication; dry friction occurs between the mechanical components, leading to severe wear. The debris generated by this wear acts as an abrasive agent that causes further damage, and this vicious cycle ultimately leads to shaft seizure. 2. Dirty refrigeration system: Dirt itself causes wear between the components of the compressor; a single particle is like a sharp knife, and as more particles are generated, this leads to shaft seizure. 3. Clogged oil filter: This causes issues with the return of oil, resulting in poor lubrication and accelerated wear, which can lead to shaft seizure. 4. Bearing wear: Wear on the bearings causes the screw to be supported off its original center, leading to an offset axis. This reduces the gap between the screw and the bearing housing on one side, thereby disrupting the lubricating effect of the oil film. Additionally, bearing wear reduces the screw’s ability to remain in place axially and radially, causing the screw to shift and causing wear on the compressor’s compression chamber and high-pressure surfaces; this can also lead to shaft seizure. 5. Oil aging: The oil is no longer able to provide proper lubrication or to remove heat, and since temperature has a significant impact on the properties of oil, this leads to a decline in the oil’s performance, increased friction, and ultimately shaft seizure. 6. Fluorine deficiency in the system: When there is a lack of fluorine, heat accumulates within the compressor, raising the temperature and reducing the viscosity of the oil. As a result, the oil cannot provide adequate lubrication, leading to wear.