EasyManua.ls Logo

CEA 4001 - Pipe Sizing and Layout

Default Icon
190 pages
Save Page as PDF
Print Icon
To Next Page IconTo Next Page
To Next Page IconTo Next Page
To Previous Page IconTo Previous Page
To Previous Page IconTo Previous Page
Loading...
43
appropriate
pressure
shown
in
Table
8
shall
be
available
at
the
level
of
the
highest
sprinklers
at
the
point
of entry
to
the
HHP
or
HHS
area
of
sprinklers.
6.3.2.3
Where
the
design
area
of
operation
is
greater
than
the
area
of
HHP
or
HHS
protection
and
this
area
is
adjacent
to
the
OH
protection,
the
total
flow
rate
shall
be
calculated
as
the
sum
of
the
HHP
or
HHS
portion when
reduced
proportionately
as
in
6.3.2
plus
the
flow
rate
for
the
OH
section
calculated
on
the
basis
of
a design
density
of
5mm/min.
The
pressure
at
the
level
of
the
highest
sprinklers
in
the
HHP
or
HHS
portion
of
the
risk
shall
be
either
that
shown
in
Table
8,
or
be
determined
by
hydraulic
calculation.
6.3.2.4
When
the
design
area
of
operation
is
fed
by
more
than
one
distribution
pipe,
the
pressure
at
the level
of
the
highest
sprinklers
of
the
design
points
shall
either
be
as
shown
in
Table
8
for
the
appropriate design
density,
or
ll)e
determined
by
hydraulic
calculation.
The
flow
rate
for
each
distribution
pipe
shall
be determined
proportionately
(see
6.3.2.5).
6.3.2.5
Where
the
basic
design
area
of
operation
for
a
given
design
density
is
increased
due
to
special circumstances,
the
flow
rate
shall
be
proportionately
increased,
(see
6.3.2.6),
but
the
pressure
at
the
design point
shall
remain
unchanged.
6.3.2.6
The
increased
or
decreased
flow
rates
shall
be
determined
proportionately
as
follows:
a
2
Q
2
=
Q
1
___
a
1
where:
Q
2
is
the
flow
rate
required,
or
in
circumstances
described
in
6.3.2.4
the
flow
rate
in
each
distribution
pipe,
in
litres
per
minute;
Q
1
is
the
flow
rate
required
as
given
in
Table
8,
in
litres
per
minute;
a
1
is
the
area
of
operation
for
design
density,
in
square
metres;
a
2
is
the
area
of
operation
required,
or
in
circumstances
described
in
6.3.2.4
the
area
served
by
each distribution
pipe,
in
square
metres.
6.4 Pipe sizing and layout
6.4.1 Pipe sizing
Pipe
sizes
shall
be
determined
in
accordance
with
Annex
G
using
one
of
the
following
methods:
-
pre-calculated
systems,
where
the
diameters
are
partly
taken
from
tables
and
partly
calculated,
using
the
method
shown
in
G.
1
and
G.2;
-
fully
calculated
systems,
where
all
diameters
are
determined
by
hydraulic
calculation,
using
the
method
shown
in
G.
1
and
G.3.
The
CEA
member
shall
decide
which
method
or
methods
shall
be
used
in
their
country,
except
that
the
following
shall
always
be
fully
calculated:
layouts
with
intermediate
level
HHS
sprinklers;
gridded
or
looped
layouts.

Table of Contents