6
4. Precautions for the Installation of Additional Fittings Before or After the
PN-COS-16
In order to ensure stable steam flow, the piping upstream and downstream of
the
PN-COS-16
must be straight runs. If the
PN-COS-16
is installed either
directly before or after an elbow or control valve, unevenness in steam flow
may result in chattering and unstable pressure.
To ensure stable steam flow, it is recommended that the
PN-COS-16
be
installed on straight runs of piping, as illustrated below.
1) Inlet (primary side) of the
PN-COS-16
(d = pipe diameter)
Maintain a straight piping run
of
10 d or more
when a
manual valve, a strainer or an
elbow, etc. is installed.
(Example: if nominal size is 25
mm (1 in), have 250 mm (10
in) or more)
PN-COS
Valve,
strainer,
elbow, etc.
10 d or more
PN-COS
Valve,
strainer,
elbow, etc.
Less than
10 d
Maintain a straight piping run of
30 d or more
when an
automated valve (on-off valve)
is installed.
(Example: if nominal size is 25
mm (1 in), have 750 mm (30
in) or more)
PN-COS
Motorized
Valve
30 d or more
PN-COS
Motorized
Valve
Less than
30 d
Maintain a straight piping run of
30 d or more
when a pressure
reducing valve is installed.
(Two-stage pressure reduction)
(Example: if nominal size is 25
mm (1 in), have 750 mm (30
in) or more)
PN-COS
Pressure
Reducing
Valve
30 d or more
PN-COS
Pressure
Reducing
Valve
Less than
30 d
2) Outlet (secondary side) of the
PN-COS-16
Maintain a straight piping run
of
15 d or more
when a
manual valve, a strainer or an
elbow, etc. is installed.
(Example: if nominal size is 25
mm (1 in), have 375 mm (15
in) or more)
PN-COS
Valve,
strainer,
elbow, etc
15 d or more
PN-COS
Valve,
strainer,
elbow, etc.
Less than
15 d
Maintain a straight piping run
of
30 d or more
when a
safety valve is installed.
(Example: if nominal size is 25
mm (1 in), have 750 mm (30
in) or more)
172-65588MA-02 (
PN-COS
Pneumatic Control Valve) 5 Sep 2014
PN-COS
Safety
Valve
30 d or more
PN-COS
Safety
Valve
Less than
30 d
Maintain a straight piping run
of
30 d or more
when a
control valve or an automated
valve (on-off valve) is
installed.
(Example: if nominal size is
25 mm (1 in), have 750 mm
(30 in) or more)
Control or
Automated
Valve
Control or
Automated
Valve
PN-COS
30 d or more
PN-COS
Less than
30 d