The paper proposes to consider the reliability of machines in terms of mass and individual production. The proposed approach makes it possible to assess the impact of various failures of machine parts on the reliability of single-purpose vehicles. Failures occurring as a result of fatigue wear are considered, but they are of a sudden nature of failure. A condition is defined to prevent such failures, from which the assigned resource to the limit state of the part must be less than the resource of each particular part that may be susceptible to sudden failure. This condition can be applied both for serial production machines and for single-source machines. An algorithm for determining sample and aggregate parameters and an algorithm for resource testing for reliability for single-source machines are proposed. The key stage for the development of the algorithm is the resource testing of machines, the carrying out of which makes it possible to objectively assess the reliability of the loaded parts. To reduce the period for obtaining test results, it is necessary to carry out accelerated resource tests of machines, which can be achieved by intensive operation of machines with short stops for inspection and maintenance. Failures resulting from tests constitute a sample that, after being processed by theoretical laws, allows the determination of the smallest values. Studies have shown that even with the estimation of sample values, the possibility of premature failure continues. In this regard, the paper proposes to use the aggregate parameters to estimate the minimum values. The use of such an algorithm will make it possible to exclude the possibility of the onset of premature failures by determining the period of operation of vehicles during which the failure-free operation of cars is guaranteed.

The paper considers the development of methods for managing the reliability of single-production machines (lunar rover, rover, rolling mill, president’s car of the country, etc.). Many years of experience in the field of machine reliability allowed the leading specialists of the department of AS and DS to develop a method for managing reliability for serial and mass machines. in the case of evaluating the reliability of single-production machines, development of algorithms based on sample data and data obtained during the transition from the sample to the set of values was carried out. The resource of the parts is defined as the main parameter, which, irrespective of their purpose, form the sampled samples of units of finite volume. Given that the main parameter of the details the resource depends on the strength and loading parameters, the correlation between the strength parameters and the acting stresses (endurance limit, active stress in the dangerous section, strength increase coefficients and the coefficient of increasing the acting voltage) is used in the studies. In such conditions, the estimated resource should relate to each entity of the population or a sample from it. During the research, a parameter is defined as the minimum resource that will determine the homogeneity of the sample (the aggregate), while the main condition for ensuring the same main parameters of parts with sudden failures is the Veler-Sørensen-Kogayev formula based on the experimental initial fatigue and loading statistics . Thus, a method has been developed to ensure the reliability of single-source machines, based on the synthesis of two methods and principles for serial and single-purpose machines.

A number of principles to ensure the reliability of individual production machines have been formulated. A block diagram of the model for ensuring the gamma-percentage target life of the individual production machine parts has been built on their basis. To assess the model adequacy, the accelerated operational tests without a test stand base have been proposed. A machine (units, parts) is considered as a system with mutually loaded elements, i.e. self-stand.

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