113 / 235
www.dklok.com
Valves
DK-LokTubeFittingCerti cationListing
DK-LokValveCerti cationListing
QualitySystemApprovals
No.V13-2
July 2013
V13W Series Bellows Valves
Severe Service Bellows Valves, Double Sealed
Working Pressure up to 2,500 psig (172 bar)
1a
Acme power
transmission thread
Back seating
2
9
11
12
3
5
1
6
7
8
10
13
16
17
Ported bonnet nut
14
15
20
18
19
Weld 1
Weld 2
18. Low Seal O-ring
(secondary seal)
Weld 3
Figure 1.
Bellows Subassembly (Primary Seal)
Features
V13W series bellows valve offers the most difficult fluid handling appli-
cations. This design with the secondary sealing system fits to the need
for a safe and reliable system.
Applications include cryogenic to high temperatures, high pressure to
vacuum in power plants, instrumentation, panels, and critical sampling
system for toxic, radioactive, and hazardous fluids.
Bellows subassembly (Figure 1)
Welding upper end of the bellows to 12. stem (weld 1) and the other
end to 19. stem weld ring (weld 2), this bellows is then welded to the
valve body (weld 3).
Bellows subassembly with the three places of welding provides all met-
al, hermetical sealed valve. This primary seal offers a complete sealing
between the system and atmosphere where leakage is not accepted.
Secondary seal (6), (18).
All welded stainless steel valves with secondary seal makes this valve
for the most difficult fluid containment applications.
Secondary sealing prevents leakage to atmosphere in the event of a
bellows rupture due to excessive pressurization. Leakage past the pri-
mary seal is contained by secondary seal.
Actuator threads (2)
Hardened 440C stainless steel actuator is for maximum strength, wear
resistance, and positive stem retraction.
Acme power transmission threads constructed on actuator (2) and the
bonnet (8) for low operation torque and to handle the extreme force
transmitted to the threads in high pressure bellows valve. The threads
are not in contact with the process fluid and are protected from atmo-
spheric containments by the packing (6).
Valve actuation
Valves in high pressure tend to stick in the closed position. The ball
bearing (9), and double pin (10) on a shoulder of stem extension (11)
provide positive lifting of stem (12) and stem retraction.
Compressing or stretching the bellows allows linear motion of the stem
with the convolutions.
Ported bonnet nut (15)
This allows monitoring sealing condition of weld 3 (Figure 1) and low
seal O-ring (18).
Turns to Open
Bellows valves operated by manual actuating bar handle requires
around 1 3/4 turns on the V13WA series and 2 1/2 turns on the V13WB
& V13WC series to open the vales to full flow.
A jam nut (4) is provided for locking the gland nut (3).
Additional Features
• Non-rotating stem disc (17).
• Standard panel (14) and bottom mounting.
• Union bonnet construction allows packing (6) replacement
for maintenance.
• Safety back-seat sealing in the valve closed position.
• DK-Lok tube fitting and socket or butt weld end connections.
• Regulating stem disc for V13WA series.