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11. TRIMMING IMPELLERS
Assembly Instructions
Fig. 11.1
Fig. 11.2 Fig. 11.3
1.
Slide impeller and inner drives with lugs on to trimming tool (PT0827) and secure with support
and bolt; Figure 11.1 and 11.2. For impeller assemblies, Slide K+ Impeller Trimming Tool,
PT0554 (Fig. 11.3) into the bushing and tighten tension disc PT0555 with bolt. This tool will
prevent lathe jaws from damaging the impeller.
2. Place the trimming tool and impeller into lathe and tighten gently, making sure to center it.
3. Adjust lathe speed to 700 RPM.
4. Slowly take roughing cuts up to 1/4" [6 mm] diameter at a time across A, B, and C as indicated in
Figure 11-1. After each cut across the impeller, carefully remove all trimmed TEFZEL chips for a
clean start on the next cutting approach. As you near the desired trimming diameter, take smaller
and slower cuts for a smoother finish.
Unless impeller is to be trimmed to smaller than 4.50" [114 mm], proceed to steps 6 and 7.
Trimming Diameters Smaller Than 4.75" [120 mm]
5.
If your impeller is to be trimmed smaller than the diameter of the sealed magnet assembly area
(i.e.4.75" [120 mm] or less), leave the back shroud (shown in Figure 11-4) at 4.75" [120 mm]
diameter and proceed to trim the front shroud and vanes to desired size.
6.
After finalizing diameter, chamfer edges A and C to approximately 0.050" x 45º [1.0 mm x 45
o
].
7.
Remove trimming tool from impeller magnet assembly and clean up any loose material with a
knife.
PT0554
PT0555
Fig. 11-4
