The article reflects information about the technology of obtaining tank shells from composite material – fiberglass. Such tanks have an extended service life due to the absence of corrosion, reduced own weight, low wettability of the surface. In particular, the influence of the winding angle of the glass fiber on the cylindrical surface is investigated. Unlike traditional materials, in the case of composite, the creation of the product occurs simultaneously with the creation of the material. Therefore, the load-bearing capacity of the structure and its resource significantly depend both on the choice of the initial components and on the technology of their connection. Therefore, the calculation of a composite product is closely related to solving the problem of its creation. Improper organization of the technical process, unsatisfactory preparation of the initial components, non-compliance with technological and many other reasons can significantly change the properties of finished products. Depending on the molding technology, the values of the properties of polymer composites may differ several times. The choice of technology depends on the design of the product, its operating conditions, the volume of manufacture and available production resources. The paper discusses some issues related to the process of obtaining a composite. The influence of the technological process on the properties of the composite is investigated, especially in the statistical aspect. The authors consider a cylindrical shell consisting of a large number of layers of glass fiber connected by a binding material. The relations are determined by which optimal material structures can be determined for other possible reinforcement schemes of the material, for example, winding in a spiral with different angles. The condition of optimality of the structure of a cylindrical shell loaded with internal pressure and axial force is determined. With the help of this ratio, it is possible to determine the optimal winding angle of the glass.