Current manufacturing trends today include additive technologies. The scope of use of industrial technological equipment for 3D-printing is expanding. Printing methods are being improved. New polymer and composite materials with reinforcement are being used. The quality, accuracy and strength of products improves. To assess the effectiveness of the implementation of technological processes in industrial equipment, the OEE (Overall Equipment Efficiency) criterion is used. For industrial 3D printing installations, the OEE indicator includes three component performance criteria: the criterion for realizing the design potential of the target technology workflow; criterion for technological assurance of product strength and quality; criterion for organizational and logistical exclusion of unproductive costs. The work has created a complete set of ways to increase the efficiency of equipment for combined FDM technologies by reducing the cost of operational time for technological and auxiliary transitions, as well as for preparatory actions for modifying polymer materials. Based on this variety of methods, the design of a multifunctional 3D printer for combined FDM technology has been proposed. The technical specifications for the printer provide for: increasing the productivity of 3D printing; ensuring adhesive strength of the connection between the initial layers of polymer material and the desktop; ensuring cohesive strength between layers of polymer material; expansion of technological printing capabilities using additional composite materials. This problem is solved by installing devices on a 3D printer that provide: modification of polymer materials by a pulsed high-frequency electromagnetic field; execution of executive robotic movements in the work cycle; computer control of all subsystems of a combined printing 3D printer using a single control program. The use of the described methods for increasing the efficiency of using 3D printers for combined FDM printing is possible in the production process of a repair and maintenance enterprise, as a set of all functions that ensure the achievement of the operating goal.