Flowserve PA46 - Manual (Page 21)

Maintenance
 continued 
Replacing stuffing box, valve seat and valve plug MPA 46, MPA 47
. Detach pressure line for the control fluid of the diaphragm actuator from the screwed socket Z.
. Remove diaphragm actuator Y. Fig. 4
3. Remove spacer disk X and pressure plate V.
4. Unscrew hexagonhead cap screws W.
5. Remove pressure plate V and mounting bracket B.
6. Pull out split pin S.
7. Use openend spanner A. F. 8 mm to unscrew the pressure pin R from the valve plug D.
8. Remove compression spring P.
9. Use openend spanner A. F. 3 mm to unscrew the union nut O.
0. Unscrew sealing plug G and remove gasket F.
. Pull out valve plug D.
. Take out internal parts N M L K L J of stuffing box.
3. Use steel punch to knock the valve seat H out of the valve body I. Fig. 7
4. Clean stuffing box, valve body and valve plug.
5. Insert new valve seat
H such that two opposite holes are in the flow direction of the intermittent
valve.
6. Use punch made of CuZn to fix the valve seat in the valve body. Fig. 8
7. Insert valve plug D and apply abrasive paste type TETRABOR ® F400 for polish grinding.
8. Insert new gasket F and screw in sealing plug G. Tighten with a torque of 350 Nm.
9. Reinsert internal parts of stuffing box according to order as specified on page 4. Fig. 5, Fig. 6
0. Apply heatresistance lubricant to stuffing box thread (use e. g. WINIX ® 50).
. Align valve plug D such that the hole for the split pin S is perpendicular to the flow direction of the
intermittent valve.
. Use openend spanner A. F. 3 mm to screw in union nut O and tighten at room temperature with
a torque of 55 Nm.
3. Apply heatresistant lubricant to both sides of the compression spring P (use e.g. WINIX ® 50) and
place it onto the union nut O.
4. Use openend spanner A. F. 8 mm to screw the pressure pin R onto the valve plug D until the
holes for the split pin S in the valve plug and the pressure pin overlap.
5. Insert split pin S.
6. Reinsert mounting bracket B and pressure plate V.
7. Insert hexagonhead cap screws W and tighten them in diagonally opposite pairs with a torque
of 20 Nm.
8. Put spacer disk X onto pressure plate V.
9. Screw on diaphragm actuator Y with a torque of 120 Nm.
30. Attach pressure line for the control fluid of the diaphragm actuator.
3. Operate the valve once.
WINIX ® 50 is a registered trademark of WINIX GmbH, Norderstedt
TETRABOR ® is a registered trademark of WackerChemie GmbH, Kempten