Double Block and Bleed Valve

This specialized double block and bleed ball valve (DB&B) is engineered for safety and efficiency. The primary Class 150 ball valve offers fast quarter-turn shut-off with reliable sealing, ideal for primary line isolation. Complementing this, the attached carbon steel needle valve enables controlled sampling and safe bleed-off. The main body of the reduced bore ball valve is constructed of ASTM A105N forged steel, with balls and stems made of ASTM A182 F316, ensuring durable performance for water, oil, and gas media within the -29~120℃ range.

The main isolation of the block & bleed valve is managed by double lever-operated ball valve among different types of ball valves, which efficiently handles primary line isolation. Its quarter-turn actuation enables quick shut-off. Furthermore, the integrated needle valve allows for safe bleed-off of trapped pressure and controlled sampling, facilitating maintenance operations. The valve's stem and gland are made from ASTM A182 F316 for reliable corrosion resistance, while the thrust gasket is PTFE and the packing is Graphite for effective stem sealing.

Durability of the block & bleed valve is built into the design, utilizing key material choices for vital components. The ball essential for assembly, is made of robust stainless steel, offering strength and reliable part. The lever for operation is a composite of 201+PVC for ergonomic handling and durability. Stainless steel, specifically SS316, is chosen for the pin and spring to prevent corrosion. The body and bonnet are both constructed of ASTM A105N, complementing the RPTFE seat material for secure, long-lasting sealing.

This dbb valve features an NPS size of 2" × 1/2". The reduced flow passage is smaller than the pipe end connection, saving installation space and cutting overall costs while maintaining stable pipeline control. Key sealing components include VITON-B O-rings and graphite packing, delivering durable and reliable tight sealing. The gland and stem are manufactured from ASTM A182 F316, ensuring structural stability and excellent media corrosion resistance for long-term service life

The robust design of this ball valve flange end ensures solid structural integrity for reliable operation under demanding working conditions. It is equipped with a 1/2" NPT carbon steel drain plug, specially arranged to realize safe draining and depressurization before maintenance. The lock gasket adopts carbon steel (C.S) material for firm and stable assembly. Furthermore, the ball is made of ASTM A182 F316, and the seat adopts RPTFE. This premium material combination guarantees tight shut-off performance and stable adaptability to water, oil and gas media.