M34.5 MUD DISCHARGE VESSEL
Mud discharge vessels are used in measuring lines with gas and fluid flow. These vessels are needed in piping, in which there is a large amount of suspended solids, sludge or solid sediments that could clog impulse piping, though it is maintained in accordance with general recommendations. At the same time these vessels are often quite needed in places, where there are secondary devices below the main pipe. In case of gas lines, mud discharge vessels are useful if measured fluid is contaminated or moist. Mud discharge vessels can also be useful in steam installations, where incrustations might be formed in impulse piping.
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
Mud discharge vessel body is designed for working pressure of 11 MPa under temperature 200 °C, 300 °C, 400 °C or 10 MPa under 500 °C. Mud discharge vessel is equipped with a shut-off valve at the outlet as a standard. The highest working pressure of the shut-off valve is determined by the type of used shut-off valve. On request mud discharge vessel can be supplied without shut-off valve at the outlet, and supplied just with weld-on socket for mounting or fittings.
Mud discharge vessel is made of stainless steel X6CrNiTi18-10 (1.4541). Shut-off valve seat is made of stainless steel X6CrNiTi18-10 (1.4541, or X6CrNiMoTi17-12-2 (1.4571). Shut-off ball valve is made of stainless steel X2CrNiMo17-12-2 (AISI 316/1.4408). On request mud discharge vessel can be equipped with a shut-off valve made of different material.
At the inlet mud discharge vessel is equipped with a socket ended with a thread or preparation for weld on diameter 20 mm, 21.3 mm or 14 mm – in the upper part (further from primary device) and at the outlet on the side of the mud discharge vessel’s body (towards secondary device). In the lower part of the vessel there is a welded-on piece ended with a thread or preparation to a welded joint on diameter 14 mm up to 20 mm for attachment of mud discharge valve. On request mud discharge vessel can be equipped with different process connection.
Method of fixing
For measurement of contaminated fluid flow mud discharge vessels are installed near primary element. For measurement of contaminated moist gases mud discharge vessels are used as condensate collectors and are installed under the device at the lowest point of impulse piping.