Flowserve G4 Sleeveline Plug Valves User Manual
Page 12
12
G4, G4ZHF AND G4R USER INSTRUCTIONS ENGLISH 5-14
1
/
2
"–4"
1. Normal procedures for field replacement of one-piece
sleeves are to be followed for inserting the sleeve,
Section V A (
1
/
2
" &
3
/
4
"), steps 1–3 or Section V B (1"–8"),
steps 1–4.
2. The firesafe top seal assembly differs from the
stan dard G4 top seal and is completed per the following
instructions.
3. The PFA diaphragm (Part 6)
is to be flared on a tapered
bar just enough to slip over
the plug stem (Figure VI-1).
SECTION VI
ASSEMBLY SPECIFICATIONS – FIRESAFE VALVES G4Z, G4ZHF, G4ZR
Note: Part number reference is shown in
Figure VI-1A.
FIGURE VI-1A
TYPICAL ASSEMBLY OF G4Z AND G4ZHF
WRENCH (13)
STOP COLLAR RETAINER (19A)
STOP COLLAR (19)
ADJUSTER FASTENERS (12A)
ADJUSTER (12)
TOP CAP FASTENERS (3A)
TOP CAP (3)
GROUNDING SPRING (17)
THRUST COLLAR (11)
PACKING GRAFOIL
®
(20)
DIAPHRAGM –
STEEL OR MONEL (6A)
DIAPHRAGM (6)
GASKET GRAFOIL
®
(21)
PLUG (2)
SLEEVE (5)
BODY (1)
O-RING* (22)
PLUG* (2)
4. The PFA diaphragm (Part 6)
is placed over the plug
stem with the lip down
using the diaphragm
guide #BY77543A and
#BY79581A (Figure VI-2).
The plug stem should
be checked for nicks
before installing the PFA
diaphragm. Nicks on this
surface could result in
scratches on the lip of
the diaphragm.
5. The metal diaphragm (Part 6A)
is placed over the plug stem
and the hole enlarged just
enough to slip down on the
stem (Figure VI-3).
7. The Grafoil packing ring
(Part 20) is placed over the
stem (Figure VI-5).
FIGURE VI-2
Place PFA diaphragm over plug stem
with lip down using the diaphragm
guide.
1
/
2''
If damaged, the
plug taper and
1/2" in length of
stem must be
repolished to a
surface finish
of 16AA on the
taper and 63AA
on stem.
FIGURE VI-1
Flare PFA diaphragm over
tapered bar.
FIGURE VI-3
Flare metal diaphragm over
plug stem with lip up.
FIGURE VI-4
Metal diaphragm is removed and
reassembled with lip down.
FIGURE VI-5
Grafoil packing ring
placed over stem.
6. The metal diaphragm
is then removed and
re placed with the lip down
(Figure VI-4).
® Grafoil is a registered trademark of Union Carbide Corporation.
*For use on G4Z-HF Alkylation valve.