ARI Armaturen STEVI 471 EN - Manual (Page 13)

Rev. 0040305000 0410 Page 13
Operating and installation instructions
Straight through control valves - STEVI
®
470 / 471
7.2.3 Replacement of the seat ring
- Remove actuator. (Refer to operating instructions for actuator!)
- Loose nuts (pos. 11).
- Detach valve top part.
- Unscrew seat ring (pos. 2) with a special wrench (can be obtained from the manufacturer).
- Clean thread and sealing taper in body (pos. 1) and apply with suitable lubricant.
- Replace respectively recondition seat ring (pos. 2).
- Install seat ring (pos. 2). (For tightening torques refer to item 7.3.2.)
- Replace gasket (pos. 8).
- Assemble valve top part.
- Secure with nuts (pos. 11) and tighten them crosswise.
(For tightening torques refer to item 7.3.1.)
7.3 Tightening torques
7.3.1 Tightening torques for nuts
7.3.2 Tightening torques for seat rings
! Refer to operating instructions for actuator concerned for
installing actuators !
8.0 Troubleshooting
In the event of malfunction or faulty operating performance check that the installation and
adjustment work has been carried out and completed in accordance with these Operating
Instructions.
If malfunctions cannot be eliminate with the help of the following table
“9.0 Troubleshooting table”, the supplier or manufacturer should be consulted.
ATTENTION !
Refer to item 10.0 and 11.0 before dismantling the valve.
M 10 = 15-30 Nm
M 12 = 35-50 Nm
M 16 = 75-100 Nm
M 20 = 80-120 Nm
DN 15/ 20 = 100 Nm
DN 25/ 32 = 150 Nm
DN 40/ 50 = 350 Nm
DN 65 = 480 Nm
DN 80 = 660 Nm
DN100 = 980 Nm
DN125 / 125v = 1450 Nm
DN150 / 150v = 2000 Nm
DN200 = 4200 Nm
-
ATTENTION !
- It is essential that the safety regulations are observed when identifying faults.