Milton CAT D7E Tier 4 Interim-Stage IIIB - Manual (Page 5)

Emissions Technology
Reliable,
integrated
solutions
Cat NOx Reduction System
The
Cat
NOx
Reduction
System
captures
and
cools
a
small
quantity
of
exhaust
gas,
then
routes
it
into
the
combustion
chamber
where
it
drives
down
combustion
temperatures
and
reduces
NOx emissions.
Aftertreatment Technologies
To
meet
Tier
4
Interim/Stage
IIIB
emissions
standards
and
beyond,
Cat
aftertreatment
components
have
been
designed
to match
application
needs.
System
components
include
a
Diesel Oxidation Catalyst
(DOC),
which
uses
a
chemical
process
to
convert
regulated
emissions
in
the
exhaust
system,
and
a
Diesel Particulate Filter
(DPF)
that
traps
particulate
matter
that
is carried
into
the
exhaust
stream.
The
DOC,
DPF
and
Cat
Regeneration
System
are
contained
in
a
Caterpillar
designed
Clean
Emissions
Module
(CEM)
that
protects
the
components,
minimizes
the
aftertreatment
footprint
and
simplifi
es
maintenance.
For
high
debris
applications
that
require
thermal
shields
on
exhaust
components,
an
optional
insulated
CEM
is
available
for
the
D7E.
Cat Regeneration System
The
Cat
Regeneration
System
is
designed
to
work
transparently,
without
any
interaction
needed
from
the
operator.
Under
most
operating
conditions,
engine
exhaust
is
hot
enough
to
oxidize
soot
through
passive
regeneration.
If supplemental
regeneration
is
needed,
the
Cat
Regeneration
System
elevates
exhaust
gas
temperatures
to
burn
off
soot
in
the
Diesel
Particulate
Filter
(DPF).
This
is
a
process
that
happens
automatically,
but
the
operator
can
initiate
the
cycle
when
convenient
or
interrupt
regeneration
as
needed.
A
soot
level
monitor
and
regeneration
indicator
lights
are
integrated
into
the
D7E
dash
display.
Key Off Regeneration
–
Optional
Key
Off
Regeneration
allows
the
operator
to
initiate
a
regeneration
cycle
after
the
key
has
been
turned
off.
If
a
cycle
takes
place,
the
engine
will
complete
regeneration,
followed
by
a
cool
down
period
prior to
shutting
down.
Delayed Engine Shutdown
–
Delayed
Engine
Shutdown
feature
is
available
to
allow
the
machine
to
cool
immediately
after
a
heavy
work
load
or
regeneration
cycle.
Engine Idle Shutdown Timer
–
An
optional
Engine
Idle
Shutdown
timer
will
sound
a
warning
and
shut
down
the
engine
after
the
machine
has
been
idling
for
a
pre-set
period
of
time.
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