Oliver Twinsafe Product Range

Floating Double Block and Bleed Valves


Our flanged style Double Block & Bleed Two Piece Valves are housed in a two piece design, and contain three valves in one single unit - thus reducing weight and saving space across the installation. The design is available in Oliver standard lengths up to ASME Class 300 and in accordance with ASME B16.10 lengths for ASME Class 600 and above.

Available up to 3" full bore and 4" reduced bore

Floating Ball design with robust lever operation

Various bleed valve options are available from our range of Instrumentation Valves, and we can work with our customers to adopt a technical project focused approach to ensure complete compatibility.

Flanged connections in accordance with ASME B16.5 or API 6A, hub connectors or welded ends also available.

Integral vent valve with threaded outlet connection.

Floating DBB Valve Specifications:
Pressure RatingASME Class 150 to 2500, API 6A up to 5,000 API
Temperature Range -50 deg c to 240 deg C
Design StandardsASME B16.34, API 6D, ASME VIII, ASME B16.5
Firesafe StandardsAPI 607, API6FA, ISO 10497
Seat MaterialsSoft Seats: PEEK, PTFE & Metal Seats: Tungsten Carbide and Chrome Carbide

2 Piece Bolted Construction

The 2 piece bolted construction provides conventional through bolting of the flanged end connections, plus the option of hub or welded ends. The overall lengths of the valve are kept to a minimum and offer considerable cost, weight and space savings over conventional piping methods of double block and bleed, using separate ball valves and spool pieces.

AMSE B16.10 overall length (ASME Class 600 and above)

Allows the replacement of single isolate ball valves with the increased safety of true double isolation, without the need for expensive pipework modifications.

Full Through Bore

Valves are available with full bore sizes in accordance with API 6D, ensuring maximum flow for increased production rates and allowing pigging of the pipe line.

Floating Ball Design

The floating ball construction ensures maximum weight and space savings, whilst providing reliable and safe isolation up to and including ASME Class 2500