One common challenge for designers of power equipment to be operated at high temperatures is the reduction of radiation heat transfer. As the emissivity factor of radiating heated surfaces of such equipment in most cases can be reasonably approximated by a constant, the power emitted by them is directly proportional to the fourth power of their absolute temperature. A solution of this problem is the use of thermal radiation shields made from low-emissivity and highly reflective materials. Traditionally heat insulation structures employ aluminum foil as such a shield. However, aluminum is soft and rather expensive, and it also has a low tensile strength. An alternative to the use of aluminum foil is the application to the external surface of the thermal insulation structure of a reflective metal layer via ion-plasma spraying (bombardment) in vacuum or metal spraying (metalizing) by means of an electric arc. In order to find out which method of reduction of radiation heat transfer offers the best results, we have compared a number of methods of thermal radiation shielding (foil winding, ion-plasma spraying in vacuum or electric arc wire spraying) in terms of thermal resistance of proper heat insulation structure. In our paper we have used heat insulation structures with thinfilm heat insulation coatings. The experiments were carried out in conditions simulating real conditions of operation of pipelines and power equipment in Russia. The results of the experiments show that the alternative methods of thermal radiation shielding are more efficient than the traditional one (aluminum foil winding). In particular, the use of an aluminum coating applied to the surface of a heat insulation structure via ion-plasma spraying allows the thermal resistance to increase by 35%; in case of metalizing via electric arc wire spraying the thermal resistance increased by 15% or more.

Syntactic foams are of interest to solve the problem of increase in the efficiency of heat supply equipment and pipelines heat insulation. The article analyses the efficiency of the use of various microspheres for syntactic foams when used for heat supply equipment and pipelines heat insulation. Moscow Power Engineering Institute has been conducting a large number of researches with the use of specific universal methods and the test stand which meets the modern requirements in order to determine the heat conductivity coefficient of various heat-insulating materials. These studies are designed to identify the impact of binding materials and microspheres properties over syntactic foams heat conductivity. The results of researches show that microspheres properties impact the heat-insulating characteristics of coatings.

The current state of the power engineering industry of the Russian Federation is characterized by high wear, low energy efficiency and the necessity for the reconstruction and modernization of a considerable amount of its energy facilities. Due to the impossibility of the construction and commissioning of a large number of facilities, the development and implementation of technologies, as well as and extending the lifespan of existing equipment in order to improve energy efficiency of power plants, remain urgent tasks. Film-forming amines are well known (Moscow Power Engineering Institute, National Research University (MPEI NRU) has been using them for over 40 years now) and are widely used in power engineering. On the basis of numerous experimental studies and industrial approbations, MPEI NRU have designed a group of technologies to address some of the problems encountered in the operation of power equipment.A wider implementation of the developed technologies will significantly improve the efficiency, reliability and service life of power units and NPP second circuits.

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