В роботі експериментально досліджена змінюваність ширини зварного шва при дуговому зварюванні у суміші захисного газу. З використанням гістограми, нормально-імовірнісного графіку, критеріїв згоди Колмогорова, Шапіра-Уілка, омега квадрат доказана адекватність застосування нормального статистичного розподілу до змінюваності ширини зварного шва.

The need for welding coordination is due to the significant risks of non-compliance with the requirements for welded joints. It is known that the request of coordination standards in welding streamlines the work of ensuring the quality of welding, it is positively perceived by customers and other stakeholders. However, the effect of systemic welding coordination on objective indicators of the quality of welded joints during production requires detailed studying. The comparative statistical analysis of the effect of systemic welding coordination on the level of welded joints' quality was preceded by the process-oriented development and implementation of a set of procedures for the coordination of welding operations in the production of welded frames. A scheme of interaction and the classification of coordination procedures in welding have been proposed. The procedures were divided into three groups. The first group includes long-term welding quality procedures. The second group is the procedures for ensuring the quality of welding in the execution of a Request (Order, Contract). The third group consists of procedures to ensure and improve the quality of welding a joint. The implementation of regulatoryorien ted content of the procedures ensures the admission of personnel with necessary qualifications, the application of appropriate welding equipment, materials, technical documentation, thermal treatment, technical control. All this together ensures that the requirements for the welded joint, the specified thickness of the main metal, the type of a joint and seam, are met. Data on the quality of welded frames during production were obtained prior to and after the introduction of the international standards of welding coordination. Using the Shewhart charts has shown that ensuring quality by the welding coordination could stabilize the welding process, translating it into a statically manageable state while doubling the proportion of nonconforming units in the sample

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Risk-based approaches are a feature of the modern quality management system. A method of optimization of product quality inspection plan by the risk of non-conformity slippage is proposed. The method is based on a risk ranking matrix, criteria of the failure mode and effects analysis (FMEA), block classification of inspection plans, approaches to non-conformity prediction, and probability multiplication theorem for independent events. The risk of non-conformity slippage was defined as a criterion of inspection plan optimization. The proposed method allows determining the acceptability of the risk, with 100 % quality inspection, in case of abandoning the inspection operation, the possibility of applying sampling and minimum sampling volumes necessary to ensure an acceptable risk level. Relationships were derived to determine the minimum required number of inspected units out of 1,000, with an acceptable risk level in product quality inspection. The initial data for the calculation are the main characteristics of the inspection plan: the probability of the object conformity with the requirements for the controlled quality characteristic, the probability of not detecting non-conformity with the provided inspection method, the rate of non-conformity slippage, which ensures an acceptable risk level. The formula allows calculating the minimum sampling volume that provides an acceptable level of non-conformity slippage risk during the implementation of the product quality inspection plan (QIP). The proposed method was tested on the inspection plan for welds of air tanks of the railway car braking system. It is possible to abandon the original 100 % inspection plan and apply sampling, which provides an acceptable level of non-conformity slippage risk. This allows reducing the volume and costs of inspection by 18 %

В роботі розрахунковим методом досліджено вплив значень параметрів розподілу Вейбула найого форму в діапазонах, характерних для змінюваності діаметру пор. Проведена адаптація ймо-вірнісної сітки до визначення параметрів Вейбулівського розподілу діаметру пор. На прикладі показано використання ймовірнісної сітки до визначення параметрів Вейбулівського розподілу діаметру пор за фактичними експериментальними даними.[dx.doi.org/10.29010/86.10]