8-4. OVERHAUL OF TURBINE ASSEMBLY.
e. Assembly And Balance of Rotating Group
To prevent injury, ensure that Insulated
gloves are worn when handling dry Ice
and cold parts
See Table 2-3, Fabricated Tools and
Equipment, for fabricating dimensions
and specifications for all FT-21XXX
numbers referenced in the text.
Place turbine wheel (20, Figure8-6) in dry
Ice and alcohol for 20-30 minutes.
Place turbine wheel (20) In fabricated tool
(FT-21616, Figure 8-11)
First dummy bearing fabricated tool (FT-
21538) is used In place of bearing (18,
Figure 8-6) In this procedure.
Heat labyrinth seal (19) and dummy bearing
fabricated tool (FT-21538, Figure 8-11) to 250-350° F
(121 1-176 60 C), approximately 20-30 minutes
Install labyrinth seal (19, Figure 8-6) and on
turbine wheel (20, Figure 8-6) shaft Secure with
antirotation pins (17).
Place labyrinth seal (29) on back of
compressor wheel (33).
Assemble compressor wheel (33) on
turbine wheel (20) shaft. Ensure that splines aline.
Second dummy bearing fabricated tool,
(FT-21538, Figure 8-11) is used in place
of bearing (18, Figure 8-6) in this
Coat dummy bearing fabricated tool, (FT-
21538, , Figure 8-11) with turbine oil and Install without
Put turbine oil under retainer nut (15, Figure
8-6) Using fabricated tools (FT-21570, FT-21571, Figure
8-11) and torque wrench, torque retainer nut (15, Figure
8-6) to 300 inch pounds (33 90 Nm)Back off and re-
torque to 50 Inch pounds (5 65 Nm)
Place fabricated tool (FT-21 540, Figure 8-
12) over assembly. Place fabricated tool (FT-21565) on
top of the turbine wheel shaft Take a base reading from
top of fabricated tool (FT-21565) to top of fabricated tool
(FT-21540) using depth micrometer Note the reading
The shaft must be stretched 0 007 to 0 009 Inch (0 018-0
023 cm) from the original reading Remove fabricated
tools (FT-21540 and FT-21565)
(10) Using fabricated tools (FT-21570 and FT-
21571, Figure 8-11) but without torque wrench, tighten
retainer nut Remeasure shaft length as described In step
(9), above Repeat procedure until 0 007 to 0 009 inch
stretch has be achieved
8-30 Change 4