Just a small amount of heat is needed to initiate the water circulation in the corner tube boilers. The water does not need to travel long distances. This means that all water-filled tubes can quickly simultaneously reach boiling point, so that thermally induced material strain is kept to a minimum.
Lower drums and other large water spaces are completely absent. This means that neither thermal stress nor any distortion connected with this needs to be taken into consideration in these areas.
Comparably few tubes are connected to the drum, so that only insignificant material weakening occurs and the drum in its entire circumference can be designed with even and comparably low wall thickness. The admissible temperature transients can thus be much higher, enabling the boiler to start up quickly.
The corner tube boiler is self-supporting. Its load is distributed between the downcomers. Within the boiler, heat expands with practically no thermal stress from the bottom upwards. The advantage of this can, for example, be seen in grate stoker furnaces, where the expansion difference between the grate and the boiler can be predicted more easily and only a simple form of sealing between the grate and the boiler is needed.
Higher load variation speeds
Load variations are possible in short intervals without the drum flooding or this leading to a deterioration of steam quality. The water level in the drum remains much more consistent than in other types of boilers.
High pressure variation speeds
Since the water velocities in the downcomers and return pipes are relatively high due to the high corner tube-specific circulation ratio, the natural circulation of the corner tube boiler remains stable, even with high pressure variation rates. The low number of downcomers and return pipes creates large, unobstructed cross-sections so that the water-steam mixture can easily flow around any steam bubbles.
High level of steam purity
In corner tube boilers, the separation of water and steam already takes place in the tube system. The moisture content/level of the steam is very low. High steam purity can be reached even with low-quality feed water.
Best use of available space
The corner tube boiler has return pipes, which supply water to the heating surfaces, not only from the drum. Thus, the heating surfaces can be situated relatively far from the drum. That is why even large boilers, such as those used in waste incineration plants or industrial power plants, can be operated without difficulty.
The boiler can be pre-manufactured in segments in the workshop. Only minimal welding on the pressure parts is needed at the installation site. This results in short installation times and low risks during manufacturing.