EFFECTIVITY
ALL CFM56 ENGINES
CFMI PROPRIETARY INFORMATION
CFM56-ALL
TRAINING MANUAL
BASIC ENGINE
PARTICULARS
BORESCOPE INSPECTION
Page 28
Sep 03
THE HIGH PRESSURE COMPRESSOR (HPC)
(ALL) :
The HPC is a 9-stage compressor mounted between the
fan frame and the combustor case.
It consists of a rotor and front and rear stators.
Front stator.
The front stator is constructed with upper and lower
cases bolted together at their split-line flanges.
It consists of :
- the inlet guide vanes (IGV’s).
- the variable stator vanes (VSV’s), stages 1, 2 and 3.
- the fixed stator vanes stages 4 and 5.
The IGV’s and VSV’s stages 1, 2 and 3 are installed
individually through the case.
There are 2 circumferential slots machined inside the
front stator case to hold fixed vane stages 4 and 5. The
vanes are assembled into segments.
Rear stator.
The rear stator case is made up of two halves bolted
together at their split-line flanges. It is installed inside the
front stator casing.
The case has internal machined circumferential slots that
hold the fixed vanes of stages 6, 7 and 8. The vanes are
assembled into segments.
Fixed vane stage 9 is part of the combustion case.
Rotor.
The stage 1-2 spool is mounted on the rotor shaft. It has
individual axial blade slots and inter-stage labyrinth seals.
The stage 3 disk supports the stage 4-9 spool and also
has individual axial blade slots.
The stage 4-9 spool is bolted onto the stage 3 disk. It
has circumferential dovetail blade grooves and inter-stage
labyrinth seals.
Each stage on the 4-9 spool has 2 blade locks to
immobilize the blades. Their position is shifted between
stages for balancing purposes.
TOC
