Plug Valve Double Block & Bleed Inspection
- “double block & bleed” with only one valve
- reliable and tight
DN 25 – 600 / PN 10-40
NPS 1 – 24 / Class 150-300
Reliably Working for our Customers
Industries
Storage • Refinery • Transport • Energy
Media
Oil • Gas • Jet fuel • Diesel • Sulfuric acid • Chlorine oxide ClO2
Functional Principle
- AZ plug valves with two self-sealing elements Block 1 and Block 2
- Closing of the plug valve seals off Block 1 and Block 2
- Open the bleed valve for tightness testing
- Inspection and revision services using inspection valves I+II
Design Features
Design Characteristics
- PTFE-sleeved plug for large sealing surface – reliable and tight
- “double block & bleed” possible with only one valve
- suitable for critical service
- long durability – adjustable plug
- outlet positions customized
- cost saving compared to 2 valve system
- alternative to traditional “lift and turn” plug valves
- Firesafe acc. to API 607 / ISO 10497 (only externally)
- TA – Luft approval
PT-Diagram
Operating temperatures < -30°C and > 220 °C have to be checked and approved by AZ according to the operating conditions.
Besides the P/T value of the sleeve the limitations of the valve bodies also have to be considered. Please refer to the EN 12516-1 resp. ASME B16.34 in order to choose a proper pressure rating (PN/class). The shown values refer to austenitic stainless steel 1.4408 (A351 Gr. CF8M).
1) For operating temperatures below -10°C low temperature / austenitic steels are required.
2) Sleeve: There are different sleeve materials / compounds available.
Materials
Standard body materials
• Carbon Steel 1.0619, ASTM A216 WCB
• Stainless Steel 1.4408, ASTM A351 CF8M
• Stainless Steel 1.4308, ASTM A351 CF8
• Unalloyed stainless steel casting (low Temp.) 1.1138, LCC/LCB/A352
Standard plug materials
• Stainless Steel 1.4408, ASTM A351 CF8M
• Stainless Steel 1.4308, ASTM A351 CF8
Special materials
• Alloy
• Monel
• Nickel
• Zirconium
• Titan
• Tantal
• other materials on request
Sealing Systems
Standard sealing for all major applications; Tmax 230°C Type STDread more [...] | Firesafe safety sealing (API 607) for fluctuating temperatures with 3x graphite packing (adjustable) for additional stem sealing; Tmax 280°C Type FSNread more [...] |
Firesafe sealing (API 607) with graphite packing for additional stem sealing; Tmax 230°C Type FSread more [...] | Firesafe safety sealing (API 607) for fluctuating temperatures with 3x graphite packing (live loaded disc springs) for additional stem sealing; Tmax 280°C Type FSN-SLread more [...] |
Chemical sealing to prevent fugitive emission of aggressive and toxic media with PTFE packing for additional stem sealing; Tmax 230°C Type CAread more [...] | Chemical safety sealing for fluctuating temperatures with 3x PTFE packing (adjustment) for additional stem sealing; Tmax 230°C Type CASNread more [...] |
Chemical safety sealing for fluctuation temperatures with 3x PTFE packing (live loaded disc springs) for additional stem sealing; Tmax 230°C Type CASN-SLread more [...] |
Port Forms
Dimensions
The valve type DBI is available in all common sizes acc. to DIN / ASME
Actuation
1 Locking Devices
Pilot valve combinations, pad lock eyelets, linear key conception, indexing plunger arrestor.
read more […]
2 Plug stem extension
Solid construction in stainless steel with T-wrench, Standard extension 100 mm or 150 mm, non standard lengths are available on request
read more […]
3 Actuators
Actuators for mounting-flange acc. to DIN ISO 5211
read more […]
NEW: Pneumatic actuator AIR GEAR for plug valves with high torque =150.000 Nm
read more […]
4 Ratched coupling
To usw on multiport valves with standard 90° actuator for bigger switchpositions than 90°
read more […]
5 Cover extension
Solid construction in stainless steel, Standard extension 100 mm or 150 mm high, non standard lengths are available on request . Hexagonal bolts on adjustment ring freely accessible. Note: Don’t use with sealing FSN/FSN-SL and CASN/CASN-SL
read more […]
Product Range
DBI-B
- bleed valve to check tightness when main valve is closed
- bleed outlet standard with “goose neck” pipe
Accessories:
- bleed outlet standard with “goose neck” pipe
- pressure transmitter
- valve automation
- locking device
DBI-B&I
- bleed valve to check tightness when main valve is closed
- inspection valve for inspection and revision services
Accessories:
- manometer/pressure gauge
- pressure transmitter
- valve automation
- locking device
DBI-B&2I
- bleed valve to check tightness when main valve is closed
- inspection valve I and II (upstream / downstream) for inspection and revision services
Accessories:
- manometer/pressure gauge
- pressure transmitter
- valve automation
- locking device
DBI-TR1
- thermal relief system to prevent pressure build-up due to thermal expansion in the plug
- isolation valve in case of service
Accessories:
- bleed valve
- manometer/pressure gauge
- pressure transmitter
- valve automation
- locking device
DBI-TR2
- thermal relief system to prevent pressure build-up due to thermal expansion in the plug and downstream pipeline
- isloation valves in case of service
Accessories:
- bleed valves
- inspection valves
- manometer/pressure gauge
- pressure transmitter
- valve automation
- locking device