Features of heat calculation in U-tube superheater of main ship boilers

Author: D.A. Shatrovsky

Abstract

In modern boiler designs, beginning with boilers of KWG34K, there is a tendency to use multi-sectional superheaters. To protect the tubes of the last section from overheating, it is recommended that heat calculation ofsuch a superheater is done with accuracy, i.e. consecutively, one at a time. As result, this helps determine what causes unequal temperature distribution behind the superheater, while enabling the correct estimation of the temperature of metal. Furthermore, it is necessary to make allowance for a larger surface than normal to obtain constant superheater steam temperature over the required range of the boiler output. However, the quantity of a steam, turning in to desuperheater, must be less 40 % of the nominal boiler output if it is located inside water drum.

Keywords: ships boiler, U-tubes superheater, section, the temperature of gases, series calculation, excess surface, water-cooled attemperator, control temperature system.

References

1. Denisenko N.I. Paroperegrevateli sudovykh parovykh kotlov [Superheaters of ship boilers]. L., Sudostroenie, 1970. — 184 p.

2. Shatrovskiy D.A. Teplovoy raschet sudovogo kotla: ucheb. posobie [Temperature calculation of ship boiler: texbook]. — SPb.: Izd-vo GMA im. Adm. S.O. Makarova, 2012. — 116 p.

3. Teplovoy raschet kotelnykh agregatov (Normativnyy metod) [Temperature calculation of boiler units (Normative Method)]. — L.: Energiya, 1973, 1998.

4. Rules for Classification and Construction of Sea-Going Ships. Part X. Boilers, Heat Exchangers and Pressure Vessels, Russian Maritime Register of Shipping, St. Petersburg, 2018.

About author:

D.A. Shatrovsky - PhD, professor, Admiral Makarov State University of Maritime and Inland Shipping, St. Petersburg, e-mail: dishat41@mail.ru

Issue: 60/61 (2020)

For citation: D.A. Shatrovsky. Features of heat calculation in U-tube superheater of main ship boilers. Research Bulletin by Russian Maritime Register of Shipping. 2020, No. 60/61, pp. 90-94.

UDC 621.184.3.4

Pp: 90-94