Are the consequences severe when steam with a very high temperature at the outlet of the steam superheater is introduced into the pipeline network?
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Are the consequences severe when steam with a very high temperature at the outlet of the steam superheater enters the pipeline network? (The specification is no more than 251 degrees) Last edited by Ma Hai on 2009-3-16 23:23]
When the steam at the outlet of the steam superheater enters the pipeline network, its temperature is very high, generally not exceeding 10% of the design value. Too high can damage the equipment.
Excessively high temperatures can cause thermal shock to the equipment; it is necessary to check whether the design temperatures of all connected equipment and pipes permit this!
Is thermal expansion taken into account in the pipeline network layout? If there is some expansion, it’s fine to have a slightly higher value as long as it remains within the limits allowed by the equipment; however, if the value is too high, not only will the equipment be damaged, but the asbestos gaskets and winding gaskets used at the connections of pipes and equipment will also deform or tear!
A temperature reducer can be added before integrating it into the pipeline network to bring the temperature within the designed range.
High-temperature steam is introduced into the pipeline network; if it exceeds the designed value, the consequences can be severe——
The temperature can be within the range specified by the design requirements, as design margins are taken into account when selecting pipes and components. Moreover, there is heat loss in the piping system over a certain length – around 10–15°C – so sufficient superheat is required to meet the pressure and temperature demands of the steam used in the process.
The steam outlet temperature of the steam superheater is 400 degrees, with a pressure of 4 MPa; if 1 is introduced. 0MPa steam pipelines must be equipped with temperature regulators and pressure reducers.
For most units, it is the case that the design value is 250, but in practice this value exceeds 250. A significant reason for this is that the steam generation capacity of the waste heat boiler is low enough to prevent the heat exchanger from cooling down, which certainly is not favorable for the operation of the steam superheater. If the material used for the tubes of the superheater is 1Cr5Mo (chromium-molybdenum), it can handle temperatures as high as 500 without any problems； If it is 20R (ordinary carbon steel), it is best not to exceed 380, as carbon steel does not have very good heat resistance and is also susceptible to sulfur corrosion.