Instruction Manual
D101554X012
Vee-Ball Valves
June 2017
45
Failure to use the correct Vee‐Ball/ shaft combination may result in the ball not being in the position indicated by the slash
mark on the end of the shaft. If the ball is not properly aligned with the slash mark, the valve will not function correctly and
seal damage may result.
6. Installing the Taper Key (key 4):
Current standard construction materials for all NPS 3 through 12 valves require the taper key (key 4, figure 14) to be
tack welded in place using the following procedure. Use standard welding preparations when preparing parts for
reassembly.
CAUTION
Make sure the drive shaft (key 6) is free of oil or grease, otherwise the taper key will not seat properly. Failure to properly
set the taper pin or taper key could result in it coming loose while in service. Loosening of the taper key in service could
result in improper valve function and equipment damage.
1. Install the drive shaft (key 6) into the valve body through the ball and into the lower bearing.
2. Insert the taper key (key 4) into ball and drive shaft (keys 2 and 6) as shown in figure 14. The taper key inserts, with
the flat side of the key, facing the drive shaft (key 6).
3. Using a flat end punch, drive the groove pin (key 7) into the ball ear and follower shaft until it is flat with the ball ear
surface.
4. Using a flat end punch, drive the taper key (key 4) into the ball ear and drive shaft (key 6) until solid, heavy contact is
obtained between the key and shaft.
5. Measure the position of the taper key head.
6. Drive the taper key in further using the minimum distance shown in table 8.
Table 9. Taper Key Minimum Depth
VALVE SIZE, NPS MINIMUM DEPTH TO DRIVE TAPER KEY AFTER INITIAL SOLID CONTACT, mm (INCHES)
3, 4, 6
8, 10, 12
4.8 (0.188)
5.6 (0.219)
Table 10. Taper Key Maximum Depth
VALVE SIZE, NPS MAXIMUM DEPTH TO DRIVE TAPER KEY AFTER INITIAL SOLID CONTACT, mm (INCHES)
3, 4
6
8, 10
12
7.1 (0.281)
7.9 (0.312)
9.5 (0.375)
10.3 (0.406)
7. Inspect the ball/shaft taper key connection to verify that the taper key spans the entire shaft flat width. If not, the
taper key must be driven in further until this condition is satisfied. However, do not exceed the maximum depths
shown in table 9.
Note
When welding standard valves that have a CG8M (317 SST) or CF3M (316L SST) ball, use 309 or 309L filler rod material.
Alloy valve taper keys are normally not welded.
8. When the above conditions are met, tack weld the taper key (key 4) to the ball ear on the head end of the key (see
figure 26). Use a:
D 1/8 inch diameter weld on NPS 3 through 6 valves,
To Next Page
Loading...
