Using the "minimum risk" method in the technical diagnosis of metallurgical equipment

Abstract

The difficult operating conditions of metallurgical equipment due to dynamic loads require special attention when designing components in the field of reliability and fail-free operation. In order to increase the reliability and durability of the spindle drive unit of the rolling stand of the hot rolling mill "1680", it is proposed to switch from "oil mist" type lubrication systems to "oil-air" type systems for bronze liners and bearings of the balancing mechanism. The oil-air lubrication principle has undeniable advantages in terms of component lubrication, flow distribution, and provides a volumetric flow of oil by injecting air into each bearing of the equipment, guaranteeing an accurate volume at each lubrication point, regardless of bearing back pressure, atmospheric pressure, temperature and oil viscosity . In order to optimize decision-making when designing new components and parts of metallurgical equipment, the vector of making reliable design decisions is increasingly shifting towards mathematical modeling of production processes and situations that arise during the performance of technological operations. It has been established that in order to determine the permissible value of the content of wear products in the form of metal shavings, one can use the general theory of recognition, which is an important section of technical cybernetics and deals with the recognition of images of any nature, namely, the "minimal risk" method. Recognition algorithms are partly based on diagnostic models that establish a connection between the state of a technical system and diagnostic signals coming from these systems. The performed calculations make it possible to accurately establish the limiting values of iron-containing impurities in the working fluid of the "oil-air" lubrication system and indicate that if the limit value x0 = 11 is exceeded, that is, if the content of iron-containing impurities in the working fluid is more than 11 g per 100 cm3, the object should be stopped for inspection and the working fluid should be cleaned by filtration. The possibility of determining the permissible value of the content of wear products in the form of metal shavings in "oil-air" lubrication systems using the general theory of recognition, namely the "minimal risks" method, which simplifies the process of setting the date of its cleaning by filtration, without burdening it with especially cumbersome formulas and calculations.