8
Forbes Marshall Thermodynamic Trap
Figure 4 : Recommended installation of Forbes Marshall Thermodynamic Trap on
mainline
6.
When a socket weld Forbes Marshall Thermodynamic Trap is being installed the welding
should be in accordance with an approved weld procedure to a recognized standard.
7.
Isolation valves should be installed to allow for safe maintenance and trap replacement.
8.
Always open isolation valve slowly until normal operation condition is achieved this will
avoid system shocks. Check for leaks and attend if any.
Note:
1.) If the trap is to discharge to atmosphere ensure it is to safe place, the discharging
fluid may be at a temperature of 100°C.
2.) For Socket weld / Butt weld end connections coat the weld ends with primer and
suitable high temperature paint immediately after welding before corrosion sets in.
6.
Start-up and Commissioning:
6.1. Flushing of lines:
Follow these steps to carry out the flushing.
1. Close the upstream trap isolation valve and open the bypass isolation valve.
2. Let the condensate drain for 10-15 minute or until clear condensate starts coming
out, whichever is earlier.
3. Now slowly close the bypass isolation valve and open the upstream trap isolation
valve.
Note:
For a detailed procedure on flushing of lines please visit Forbes Marshall website.
6.2. Commissioning:
After installation or maintenance ensure that the system is fully functioning by confirming
condensate is passing through it.
1. After flushing of lines is complete, ensure that bypass isolation valve is closed and
upstream trap isolation valve is opened.
2. Check for leaks and attend if any.
Mains
diameter-D
diameter-d
1
depth-d
2
Upto 100mm
d = D
1
Min d = 100mm
2
125-200mm
d = 100mm
1
Min d = 150mm
2
250 mm & above
d > D/2
1
Min d = D
2
D
d
2
d
1
Steam mainline
FMTD54M
Hot condensate
to return or drain
To drain
