Page 435 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

Steam lfrrbines and TUrb0e;lqMners 413

Clearances (Refer to Coupling Detail Figure 8-20)

1. Maintain .065 in. to -075 in. (1.7 mm to 1.90 mm) gap between the
coupling (6) and the ball head adapter.
2. Adjust gap “A” to maintain the coupling sleeve axial clearance .030
to .060 in. (.76 to 1.5 mm).
3. Maintain the coupling sleeve axial clearance float of .030 to .060
in. (.76 to 1.5 mm).

Note: Proper float of .030 to ,060 in. (.76 to 1.52 mm) is to be
maintained to protect the TG-10 governor from any turbine
shaft thrust and thermal expansion loads, and to ensure suf-
ficient coupling tooth engagement.

Governor Instalatlon

1. Assemble with the steam end bearing cap (22) removed. (The cou-
pling can be inspected with this cap removed and “A” clearance
can be checked.)
2. Place the key (5, Figure 8-20) and coupling flange (6) on the trip
body (23).
3. Install the coupling flange (6) on the trip body (23) allowing .080-
.090 in. (2.03-2.29 mm) clearance between their vertical sur-
faces. Snug up set screws since the flange will be repositioned
later to obtain “A” clearance.
4. Install coupling sleeve in the coupling flange.
5. Mount governor adapter (1) into machined groove on bottom half
steam end bearing casing.
6. Place the key (5, Figure 8-20) and governor flange on the governor
drive shaft.
7. Adjust the coupling flange to provide the proper clearance between
the flange and the ball head adapter and lock the flange in place by
tightening the set screws. (Coupling detail, Figure 8-20).
8. Mount the governor (2) on the adapter (1) making sure the cou-
pling sleeve engages the governor coupling flange.
9. Replace the four cap screws (4) to secure the governor to governor
adapter.
10. Loosen the set screw and slide the coupling flange up tight against
the coupling sleeve and the locked governor flange. Measure the
gap between the coupling flanges, “A” dimension.
11. Add the float -030 to .060 in. (.76 to 1.52 mm) to this gap (mea-
sured in previous step) and then reset “A” to this clearance.
Tighten the flange setscrew and recheck the float.