| PROPER
INSTALLATION PROCEDURE
|
 |
IMPROPER
TECHNIQUES |
|
| Pipework
opened to allow free valve entry with the disc in a semi-closed
position.
|
Pipework
not spread sufficiently - could tear rubber seat. Disc in open
position will hit flange and score disc edge.
|
| Valve
in semi-closed position to (1) protect disc edge, (2) reduce
rubber interference during installation and start-up, and (3) help
reduce initial torque build-up.
|
Disc
as shown in fully closed position causes seat distortion. When
flanges are drawn up, rubber will close around disc edge creating
excessive torque in initial operation.
|
| Disc
should be turned to full open position after flange alignment and
before evenly pulling up flange bolts.
|
Incorrect
pipe alignment will cause interference between disc edge and
flange face creating leakage and excessive torque for opening
valve.
|
