Einbau- und Betriebsanleitung
Installation and Operating instructions
Instructions de montage et de service
5751-8010
21
07/2013
Do not use grease or lubricants in combination with graphite packing!
6.3.4
Plug assembly
Withdraw the Integral plug assembly (12). If the plug(12) shows no signs of water and tear, then it may be re-used.
Replace piston rings (4) and all graphite seals & packings, any time that the unit is disassembled. Take care not to overstress the piston
rings(4) when fitting.
7
Maintenance
7.1
Spindle packing
Generally spindle packings have to be changed or tightened immediately (for pure graphite assemblies), new packings can
otherwise leak again after a short period.
The design of the spindle packing is described in the technical data sheets. Spindle packings are available as spare parts set
from the manufacturer. When ordering spindle packing always state the valve serial number ("W. Nr."). This is on the
identification label that is attached to the cross carrier plate.
7.2
Changing stuffing box packing
Release pressure from valve and discharge piping according to regulations
The actuator must be removed to exchange the spindle packing. Assembly and disassembly of the actuator are described
in the operating instructions of the respective actuator.
Inspect the stuffing box and stem straightness. Wear, Scratches, pitting and other abnormalities which would prevent
establishment of a good seal around the packing. A smooth undamaged surface is essential a good sealing.
Packing is supplied as a complete set ring should be in same order as packaged in the set. Install packing set in correct order.
Check the packing rings (15) for proper fit. They should be push fit into stuffing box.
Install one ring at a time, in the proper sequence, using a packing driver or gland bushing.
Tighten the gland nuts to recommended torque.
Attention!:
Tightening the pure graphite assembly too much may cause high friction, which can impair the functioning of the
control valve.
7.3
Changing plug assembly
We recommend renewing the spindle packing at the same time as replacing the plug assembly. Replacement of soft kits is
required when replacing the plug assembly.
Release pressure from desuperheater and discharge piping according to regulations
The actuator must be removed to exchange the plug assembly (please refer to the operating instructions of the respective
actuator).
Remove the packing flange (17), top guide(16),all packing rings (15),bottom guide(14) from the body.
and finally remove cone assembly from housing (101) and replace with the new one.
Clean housing seal areas
Place the packing flange (17), top guide(16),all packing rings (15),bottom guide(14) .Place cover (201) and screw tight in
crosswise order (for tightening torque see table in appendix)
Mount actuator onto valve according to operating instructions and check limit stops.
7.4
Changing nozzles
We recommend renewing the stuffing box packing when changing the nozzle pipe.
Release pressure from valve and discharge piping according to regulations
Remove the tack weld on the nozzle and unscrew the nozzle using the two pilot holes.
Remove the grafoil seals without damaging the internal surface.
