Intracottle water treatment
When checking the entries in the logbooks and from a conversation with the ship's mechanics, the audit team found that the use of these antinakipins is mostly purely mechanical, without a clear understanding of the nature of the chemical and physical processes taking place.
There is particular confusion regarding the units of measurement for the alkalinity of boiler water. So, if the salinity of boiler water is calculated in Brandt degrees and varies between 6-8 Brandt degrees on different ships, then with regard to alkalinity — the sodium number — in the engine logs, there are often entries such as "sodium number 1.58 °" or "1.6 °", etc. Mechanics don't know what such a "degree" of a neural number means. In fact, this value is not a sodium number, but the degree of saturation of the boiler water with the corresponding antinakipine, and the ratio between these degrees and the sodium number will be different for different preparations. Such confusion in the system of in-boiler water treatment is, at best, absorbed by ship mechanics purely mechanically and does not reveal the actual quality of boiler water in our measurement system.
The opening of the boiler hatches in various rows of tubes, as well as the sump hatches and a thorough internal inspection of the boilers showed a fairly effective effect of these antinakipins. On most ships, the internal surfaces of boiler tubes and sump tanks, after their continuous operation for 1700-2000 hours, were completely free of scale and oil and only covered with a thin reddish coating (traces of antinakipins).
Along with this, on some ships (the steamer, where the chief mechanic is T. Gnasyuk, et al.), small accumulations of sludge were found in many tubes and sump tanks. An analysis of this phenomenon suggests that it is this sludge that is the cause of overheating, deflection and bulging of the lower row of tubes that occurred on some ships (steamships where the mechanics of the tt. Penkov, Gnasyuk, Vasiliev, Zvorono, and others). However, the process of sludge formation and these minor accidents are irregular and, as they are not widespread, have not yet been explained. Presumably, they are caused by insufficient water circulation in these boilers, especially at low loads, when the circulation flow moving through the tubes at low speed is unable to flush the sludge deposited in the tube. The formation of sludge on some ships is most likely the result of an irrational boiler purge regime. Rainbet