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A comparative description of the technology for producing blanks for the artillery shell cases or the rocket shell bodies using flat rolled stock or rolled tubular products is given. It is noted that the lower cost of flat rolled stock leads to its wider application for stamping blanks of cartridge caps or bodies, including cutting a circle from flat rolled stock, convolution and several transitions of drawing, alternating with heat treatment. It is noted that the disadvantage of this technology are the errors in the shape of the blanks, amounting to 0.75÷1.5 of the tolerance for diametrical dimensions. When machining, these errors decrease according to the laws of copying the errors, however, the anisotropy of the material of the part blank leads to the appearance of errors in the shape-ovality and curvature of the pipe, which lead to the formation of a large radial runout of the prefabricated rocket body. It has been found that the scattering fields of all output quality parameters exceed the existing tolerances: radial runout of the assembled body by 1.3 times; ovality of the middle centering bulge by 2.15 times. It is shown that the technological process of manufacturing prefabricated housings using initial blanks from flat rolled stock does not provide the required precision technology reliability. For the manufacture of monolithic extended axisymmetric bodies, hot-rolled thickwalled pipes are used as an initial billet. The operations are performed in the following sequence: cutting pipes into dimensional workpieces; machining (turning, boring); heat treatment (quenching, tempering); machining (fine turning, boring); rotary drawing (first and second transitions); crimping the thickening; low temperature annealing. Statistical studies have found a regression equation showing at a confidence level β = 0.95, dependence of the diameter of the base hole of the workpiece after drawing in from the current value of the diameter before drawing.

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The authors of the article propose a way to increase the accuracy of processing pipe casings included in special products. Currently, in the current production of these products, there is a need to increase the accuracy of manufacturing cases, so it was decided to conduct research work. The article discusses the process of processing long bodies from thick-walled workpieces using hoods, which ensures high precision workpieces and minimal impact on the properties of the initial type of workpiece. As a result of the research, the significance of the geometric errors of the component pipes of the product on its functionality is analyzed. The achieved accuracy of the manufacture of base surfaces and the parameters of their possible distribution are shown. The similarity of the parameters of the initial part and further assembly is determined, it is also shown that the runout of the end surfaces of the part has a significant effect. The optimal basing scheme for finishing the end surfaces of long bodies is shown.

Показано влияние погрешностей положения стыковых поверхностей собираемых деталей про-тяженного осесимметричного корпуса на погреш-ность положения исполнительных поверхностей. Определены параметры законов распределения погрешностей положения стыковых поверхностей базовой детали. Отмечена взаимосвязь параметров базовой детали и сборки, причем установлено, что превалирующее влияние имеет торцовое биение. Обоснована необходимость коррекции технологии окончательной обработки торцов базовой детали.Ключевые слова: погрешность положения, стыковые поверхности, базовая деталь, исполни-тельные поверхности, закон распределения по-грешности, сборка.