M24.17 CONDENSATION VESSEL
Condensation vessels are used in the steam flow measuring circuits. Their task is to ensure steady impulse pipe filling with a steam condensate in the same height. Therefore condensation vessels are placed directly at the outlets of primary elements so that they were in horizontal position, which eliminates erroneous additional differential pressure otherwise arising as a result of unequal suction heights. Their large inner volume enables minimized fluctuation of condensate level. Fluctuations of its level adversely affect measurement accuracy.
Size of the condensation vessel is determined with respect to requirements of ISO 2186 as well as with respect to temperature and pressure of the steam in the main pipeline.
Limits of use and design
Condensation vessel body is designed for working pressure of 16 MPa under temperature 540 °C. Condensation vessel is equipped with a shut-off valve at the outlet as a standard. The highest working pressure of the shut-off valve is 12 MPa under 550 °C. On request condensation vessel can be supplied without shut-off valve at the outlet, and supplied just with weld-on socket for mounting to impulse piping.
Condensation vessel body as well as shut-off valve is made of refractory alloyed steel 13CrMo4-5 (1.7335). On request condensation vessel can be equipped with shut-off valve made of different material.
At the inlet condensation vessel is equipped with a sleeve ended by preparation for welded joint on diameter 20 mm, 21.3 mm or 14 mm. At the outlet it is equipped with welded-on shut-off valve ended by preparation to the welded joint of diameter 14×2.5 mm or 21.3×3.2 mm. On request condensation vessel can be equipped with other process connection.
Method of fixing
Condensation vessels are fixed directly on the outlets of primary elements so that the outlets were in the same level – condensate level in the condensation vessel has to be in the same level. (1mm difference of level causes measurement error in differential pressure of 10 Pa) If condensation vessels are installed on primary elements in vertical piping, it is essential to install both condensation vessels at the same level, preferably in the level of upper tapping. Fully functional vessel radiates heat into the environment therefore it may not be isolated. Temperature is dependent on pressure of condensate in the vessel.