Survey algorithm for cold and hot water supply systems of residential buildings

Introduction. Currently, there is a wide variety of methods for monitoring the condition of pipeline systems which require a different set of equipment. However, these methods are not applied for internal water supply systems due to restrictions on pipe diameters and complicated availability of communications

Materials and methods. To assess the corrosion activity of water and determine the possibility of calcium carbonate release, various indices can be used: Langelier, Risner, Snow-Jackson, etc. When monitoring water supply systems with signs of corrosion using an electron microscope, it was found that the composition of the corrosive sediment contains a large amount of zinc, and, in some cases, copper. The essence of the proposed method is that a preliminary prepared steel indicator sample cut from an uncoated pipe was placed in a container under a stream of cold or hot water in the investigated water supply system made of galvanized steel pipes (including copper-containing fittings and heat exchangers), the sample was kept under the stream for 3–4 hours until the formation of surfaces of firmly attached corrosion products (sediment).

Results. Fistulas were found on horizontal sections, on turns, in places where pipelines are welded. When laying pipes in parallel in a horizontal plane, it is necessary to bypass the pipes located next to the risers, which leads to the appearance of U-shaped or U-shaped contours of horizontally laid pipes. The most obvious reason for abnormally rapid corrosion in horizontally arranged pipelines with a U-shaped connection scheme of risers is the low speed of water movement. At low velocity of water flow in pipes with a change in the direction of water movement from horizontal to vertical and down, air will accumulate on the horizontal section of the main pipeline, while sediment will accumulate on the horizontal section going to the riser.

Conclusions. The experience of the survey of water supply systems of buildings shows that, first of all, it is necessary to assess the impact of water quality on corrosion of pipelines according to stability indices, which in some cases can provide an answer to the possibility of abnormally rapid corrosion.

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