172-65613A-03 (DR8-3P/DR8-3EP/DR8-6P/DR8-6EP) 11 Jun 2020
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5. Piping Size
If the secondary steam flow velocity is expected to be more than 30 m/s (100
ft/s), install a diffuser in order to keep the flow velocity below 30 m/s (100 ft/s).
If the distance between the DR8 and the steam-using equipment is great, a
possible drop in pressure should be taken into consideration when selecting
the piping size.
Diffuser
DR8
Straight piping: 10d or longer for
primary side,15d or longer for
secondary side (d=pipe diameter)
DR8
Primary
Side
Secondary
Side
Pressure
Gauge
Inlet
Valve
Bypass Valve
Safety Valve
(Relief Valve)
Outlet
Valve
Pressure
Gauge
Steam
Trap
Bypass Valve
Secondary
Side
Safety Valve
(Relief Valve)
Outlet
Valve
Pressure
Gauge
Primary
Side
Pressure
Gauge
Inlet
Valve
Steam
Trap
6. Two-stage Pressure Reduction
Employ 2-stage pressure reduction if the required reduction is not possible due
to DR8 operating range limitations (when it is not possible to reduce to the
desired pressure using a single pressure reducing valve).
DR8
Pressure
Gauge
Inlet
Valve
Outlet
Valve
Pressure
Gauge
Inlet
Valve
Bypass Valve
Bypass Valve
Safety Valve
(Relief Valve)
Outlet
Valve
Primary
Side
Secondary
Side
Bypass Valve
Inlet
Valve
Outlet
Valve
Pressure
Gauge
Pressure
Gauge
Pressure
Gauge
Steam Trap
Steam Trap
Secondary
Side
Steam Trap
Primary
Side
Safety Valve
(Relief Valve)
Pressure
Reducing
Valve
Pressure
Reducing
Valve