Double Block and Bleed Valve Series DBB-C and DBB-F

The product

There are structural constraints that are also very important, such as keeping the structure as light as possible, and there are obvious benefits from making components smaller and lighter. Construction site job is also very expensive and any reduction in installation manpower is also beneficial. The above situation has led to the modification of the patterns of valve components to incorporate savings in space, weight, and labor costs where possible, while still retaining the original function of the valve.

The greatest savings are to be seen in the reduction of leak to atmosphere because the potential leak points are minimized compared to the conventional design. Process isolation philosophy has become more complex as safety issues have to be addressed and the requirement for double block and bleed isolation has become more commonly used. Double Block and Bleed isolation requires two in-line isolation valves and a bleed valve, used to drain or vent trapped fluid between the two closure elements.

Size & Rating

Features

• Live Loaded Gland Packing

Graphite Packing are provided as standard taking care of Fire Safe Design Condition. Belleville Springs Washers are used to achieve live loading which protects Gland loosening under vibrations & shock conditions.

• Double ‘D’ Stem to Lever Connection

Stems are Designed to have Double ‘D’ Connection at the top for Lever Fixing. This feature eliminates possibility of Lever Assembly in the wrong direction as the Lever indicates the Valve Position once installed on the line.

• Equalized Cavity Pressure

The Pressure equalization hole at the top of the Ball combined with Seat Design are Engineered to maintain the Pressure balance in the line & in the Body Cavity irrespective of Valve Position.

• Antistatic Device

To ensure Electrical Continuity between the Stem and Ball and Body all Valves are provided with Antistatic device as an integral part of Floating Ball Valves.

• Blow Out Proof Stem

Stem is Designed to include a collar to provide protection against Blow Outs.

• Locking Device

Locking devices are provided on all Valves with both Lever Operator ad Gear Operator.

• ANSI B16.5 flanged inlet connections 1/2″ to 20″ sizes.
• Class 150 rated to class 2500 rated.
• 1/2″-14 to 1″-11.5 NPT (female) standard outlet (depending on bore size).
• 1/2″ NPT (female) standard vent.
• Standard materials of connection: Stainless steel ASTM A182 F316/F316L, WCB & CF8M, Carbon steel ASTM A350 LF2/A105, Duplex ASTM A182 F51.
• Optional materials on request. Stainless steel ASTM A182 F316/F316L.
• Carbon steel ASTM A350 LF2/A105. Duplex ASTM A182 F51.
• Raised face and ring type joint flange face styles.
• One-piece forged construction flange as standard. Fire safe designed (and tested) to meet BS 6755 Part 2/API 607.
• 304 stainless steel handles and trim as standard to reduce the risk of corrosion when required .
• Designed to meet the pressure and temperature requirements of ASME/ANSI B16.34/B16.5.
• Pressure boundary designs calculated to ASME VIII Div 1 and verified by testing. Heat code traceable material to EN 10204.3.1.
• Bubble tight shut off.
• locking and anti tamper devices for all valve types available option.
• Positive lever stop. User preferred handles. Permanent affixed reference label.
• Cryogenic application valve available.

Standards

Technical Specifications

Application Industries

• Petrochemicals
• Oil and gas
• Chemicals & Natural Gas
• Low temperature and LNG