Double Block and Bleed Ball Valves are aimed to get a double barrier on the piping, and bleed the fluid trapped between the two balls from a dedicated drain line. Body construction can be either forging or centrifugal casting. Wide range of materials: carbon steels, austenitic or martensitic SS, duplex-superduplex SS, nickel-based alloys.

Main parts

Valve design can be either Trunnion or Floating type, anti blow-out stem and typically SPE seat design. Drain port is normally provided with a floating ball valve, to be fitted with Final User drain line. Valve seats can be soft or metal to metal hard-faced.

Main reference codes:
Standard design in accordance with API 6D / ASME B16.34 / API 6A.
Antistatic design as per API 6D and ISO 17292.
Valve ends can be flanged (RF, FF, MF or FF, RTJ), according to ASME B16.5 (up to 24¡±) , Butt-Welding according to ASME B16.25, or Hub, according to customer Requirements.
Fire Safe according to BS6755 / API 6FA / API 607, since each sealing point is provided by a secondary fire-safe seal in graphite. Valve soft seats also are provided with secondary metal-to-metal seal in case of fire.
Double Block and Bleed ball valves are typically manual operated, but can be equipped also with an actuator (electric, pneumatic, hydraulic).

- Maximum Operating Pressure: Class 2500(6000 psig) @ 100 F degree (38 C degree)
- Operating Temperature Range: PEEK Seat : -65 F degree (-54 C degree) to 400 F degree (205 C degree)
  PCTFE Seat :  -22 F degree (-30 C degree) to 356 F degree (180 C DEGREE) 

The following optional features are available:

Locking device.
Emergency stem seal injection;
Emergency seats sealant injection;
Weld overlay (316 or Inconel 625) on dynamic sealing areas or in all wetted parts
Removable supports;
Certified lifting devices;
Seal welded fittings.