Analysis of the causes of failure of pumping equipment based empirical data

Pumping equipment of petrochemical factories works in the chemical exposure and high temperatures of the pumped flows. Thus, the actual problem is the reliability of the circulation pumps. This paper analyzes the statistical information on mean time to failure and types of defects that lead to failure of the hot pump petrochemical plant. According to available data of operational period of the unit before each failure were obtained histograms of density functionof failure distribution for the analysis the reliability parameters of pumps operation. Also were determined main principals for increasing of reliability of pump equipment.
Materials and methods
In article were used the production experimental data for processing and confirmation of the results, mathematical methods of representations illustrative information and validation of the results.
Results
The paper presents the results of the analysis of statistical data on failures of circulation pumps designed for pumping hot liquids (with temperatures exceeding 115°C) on the example of the chemical plant. It is obtained that the main cause of pump failure is "stuck rotor", which accounts for 66% of the total number of faults. The "stuck rotor" was due to thedestruction of the elements of the pump-bushings, liners, rings or bearings.The average time to failure of the pumps for sodium sulfate environment amounted to 5498 hours, and for pumps where the working environment is alkaline, the average time to failure is much lower and amounted to 2324 hours.
Сonclusions
Based on the statistical analysis of density function of failure distribution of pumpswas revealed that is obeys to Weibull's two-parameter rule. Circulation pumps are operated under conditions of chemical action and high temperatures of the pumped flow, it is therefore necessary to continuously control the probability of failure-free operationand to take measures for maintenance orto maintain a constant sufficient amount of spare parts in the case of non-repairable components.