Steam Operation; Start-Up; Setting The Pressure - Mankenberg DM Originalbetriebsanleitung

Original operating manual
Pilot-controlled pressure regulators DM
Recommended installation for steam
1 Strainer
2 Shutoff valves
3 Pressure reducer
4 Safety valves
5 Pressure gauge
6 Sense line
7 Leakage line
8 Expansion tank
9 Water trap (Steam dreyer)
10 Steam trap
11 Bypass for maintenance
Sense line connection 10 - 20 x DN
behind the valve
In case the valve must be emptied completely during operation (angle valves), it must be installed with the
spring cap pointing upwards.

14.13 Steam operation

If a pressure reducer is installed in a steam plant the diaphragm water reservoir must be filled before the plant is
started up. There must be no danger of overheating at the installation site caused by excessive ambient
temperatures or insufficient heat dissipation. Pressure regulators must not be insolated. In some cases an
insulating of the body is permitted, but only with cast bodies. Never insulate diaphragm housing, mid section
and spring cap (or open springs). Overheating caused by insulating destroys the elastomere of the control unit.
Many steam generators send a lot of water through the piping together with the steam. Even an initial
overheating can get lost through piping heat losses, so that the steam gets "wet". A piping speed of up to 25 m/s
is normal for "dry steam", whilst wet steam already has the effect of a sandblasting machine at this speed, and
the condensate and/or the water droplets eat holes into pipings and valve seats. In addition, water obstructs
heat transition especially in heat exchangers. To avoid it, the water should be removed by a water trap, also
called steam dryer, as quickly as possible and without steam losses.

14.14 Start-up

Pressure reducers should be started up and operated without pressure surges, if possible. A sudden operation
of upstream or downstream valves should be avoided.

14.15 Setting the pressure

Pressure reducing valves are normally supplied by us with a relaxed spring. This means that a valve is set at
the factory to the minimum outlet pressure. The required pressure should be set under operating conditions.
DM-4.X.222 Issue 18.07.2022
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