Val-Matic Cam-Centric Plug Valve - Manual (Page 9)

9
WARNING: Open valve and drain line before
removing cover bolts or pressure
may be released causing injury.
Place plug in lowest position
before removing actuator or plug
may rotate suddenly and jam or
damage plug surface.
ITEM DESCRIPTION MATERIAL
1
Housing Cast Iron
2 Wormwheel Ductile Iron
3 Worm Steel
4 Cover Cast Iron
5 Indicator Cast Iron
6 O-Ring Buna-N
7 Roller Bearing Steel
8 Shaft Bearing Bronze
9 Shaft Steel
10 Gasket Fiber
11 Handwheel Steel or Iron
12 Operating Nut Iron
13 Chainwheel Iron
14 Cover Bolt Steel
15 Indicator Bolt Steel
16 Pipe Plug Steel
17 Pin Steel
18 Spirol Pin Steel
19 Spring Pin Steel
20 Screw Steel
21 Jam Nut Steel
22 Plug Steel
23 U-Cup Seal Buna-N
TABLE 5. GEAR ACTUATOR PARTS LIST
TROUBLESHOOTING
Several problems and solutions are presented below to
assist you in troubleshooting the valve assembly in an
efficient manner.
• Leakage at Valve Shaft: Adjust or replace packing.
• Leakage at Flanges: Tighten flange bolts, replace
gasket.
• Valve Leaks when Closed: Pressure should be in the
direction of pushing the plug into the seat. Adjust
plug position by rotating the handwheel. Inspect plug
for damage and replace.
• Hard to Open: Flush debris from valve. Check
interior of valve for grit buildup or debris. On buried
valves, check alignment of operating stem.
• Leaking Oil: Tighten actuator cover bolts. If leak
persists, remove actuator cover, inspect grease, and
replace actuator gasket.
• Noisy Operation: Flow noise is normal. Loud flow
noise similar to hammering may be cavitation from
dropping high pressures across valve; review
application of valve. For gear actuator noise, inspect
grease; add new grease if there are uncoated
moving parts or grease has broken down into oil.
DISASSEMBLY
Disassembly may be required to inspect the plug for
wear or remove debris and deposits from the valve.
Work on the valve should be performed by a skilled
mechanic with proper tools and a power hoist for large
valves. The valve can be disassembled without
removing the valve from the pipeline. Refer to Figure
14 for valve construction and parts.
1. Open valve and drain the pipeline. Close valve
until plug just touches the seat. Remove the small
cover on the actuator to expose the shaft key.
2. Remove the actuator mounting bolts and lift
actuator from valve taking care not to lose key
(24).
3. Remove cover bolts (15). Matchmark cover (2)
and body. Screw eye-bolts into actuator mounting
holes and use hoist to lift cover (2) and plug
assembly from valve. Use caution to prevent plug
from dropping while lifting cover. To remove plug
(3) from valve, use sling around top portion of
plug.
4. Inspection of the bearings (6) is done by
measuring diameter of shaft and inside diameter of
bearing. Check for a normal running clearance of
.005". Bearings are permanently lubricated.
5. Thrust bearing assembly (23) and packing gland
(18) can be removed by removing all of the hex
nuts (12).