Paint and varnish coatings for protecting mechanical equipment for river hydraulic structures against corrosion: Fid-Bau Portal

Paint and varnish coatings for protecting mechanical equipment for river hydraulic structures against corrosion

Chesnokov, B. S. / Gurevich, Yu. M. / Litvak, M. L. / Puchkova, M. I.

Conclusions 1. As a result of seven years of research and experimental work we can recommend chlorinated polyvinyl chloride, ethynolic, and epoxy coatings for corrosion protection of submerged mechanical equipment of river hydraulic structures. The recommended schemes of protective coatings are given in Table 1. On using the data in Table 1 it should be taken into account that primer KhS-010 can be replaced by primer FL-03k or FL-03kk; 3% aluminum powder is added through the layer to varnishes KhSL and KhS-76. 2. The economic expediency of using chlorinated polyvinyl chloride coatings is also confirmed, since the requirements for corrosion protection will be lower than for ethynolic and coatings of Kuzbasslak, although the initial unit cost of the coating will be higher. Table 2 gives the approximate cost (with consideration of assembly operations) of protecting 1 m2 of flat gates or trash racks of the usual channel power station referred to a 30-year service life, and Table 3 gives the unit cost of applying a coating to 1 m2 of surface. The economic efficiency of the coating with the higher initial cost is explained by the fact that the total expenditures for corrosion protection depend on the complexity, volume, and cost of concomitant operations, mainly, on the frequency of necessary restoration of the coatings. The more difficult it is to accomplish these operations and consequently the higher their cost, the more advantageous it is to use the more durable, although more expensive material. When selecting protective materials one should take into account not only the conditions under which the mechanical equipment operates but also the conditions of performing operations on the repair and restoration of the destroyed protective coating, and one should select from the recommended materials and schemes of coatings those which provide a reduction in expenditures for corrosion protection of equipment for a prescribed service life.