Pneumatic Double Offset High‑Performance Wafer Butterfly Valve is a high‑performance butterfly valve featuring double‑offset structure and driven by pneumatic actuator. The stem axis creates dual offsets relative to both the disc centre and sealing centre. This enables the disc to lift off the seat rapidly during opening and closing cycles, substantially reducing friction and wear between disc and sealing surface, so as to improve the valve’s service life and sealing performance.
Working Principle of Pneumatic Double‑Offset High‑Performance Wafer Butterfly Valve:
Opening Process: The pneumatic actuator drives the stem to rotate. The disc lifts off the seat quickly after rotating only a few degrees. Throughout the 90‑degree operating travel, the disc keeps separated from the seat for most of the stroke with barely any scraping or wear.
Closing Process: The sealing face of the disc contacts the seat only when approaching the fully‑closed position. Sealing is achieved by wedging force generated from double offset geometry pressing the disc against the seat. Higher medium pressure delivers tighter sealing contact to realize reliable bi‑directional shut‑off.
Double‑Offset Structure: The first offset shifts the stem axis away from the disc centre; the second offset further offsets the stem axis from the valve‑body sealing centre. This produces a cam‑type lift‑off and wedging effect during disc rotation, minimizing sliding friction and wear on sealing surfaces.
Pneumatic butterfly valves are widely used in industrial piping systems for fast, automatic and reliable flow isolation and regulation. Equipped with pneumatic actuators, these valves enable remote operation and can be integrated with PLC, DCS and automatic control systems for efficient process control. Key parameters including working temperature, medium, pressure rating, valve size, actuator type and connection standard should be confirmed before ordering to ensure proper valve selection. Customized valve sizes, pressure ratings, connection types, sealing materials, body materials and pneumatic actuator configurations are available for various industrial and non-standard applications. (Unit: mm)

| DN | NPS | Type/Class | Part No | A | B | C | F | L | h | P | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 50 | 2 | D672-150LB | D672P150XLX2 | 50 | 86 | 70 | 100 | 44 | 14 | 7 | |
| 65 | 2.5 | D672-150LB | D672P150XLX2.5 | 59 | 105 | 81 | 117 | 48 | 27 | 11.2 | |
| 80 | 3 | D672-150LB | D672P150XLX3 | 73 | 115 | 92 | 131 | 48 | 27 | 11.2 | |
| 100 | 4 | D672-150LB | D672P150XLX4 | 95 | 131 | 110 | 157 | 54 | 27 | 11.2 | |
| 125 | 5 | D672-150LB | D672P150XLX5 | 111 | 138 | 119 | 185 | 57 | 27 | 11.2 | |
| 150 | 6 | D672-150LB | D672P150XLX6 | 142 | 151 | 134 | 216 | 57 | 27 | 14 | |
| 200 | 8 | D672-150LB | D672P150XLX8 | 188 | 186 | 171 | 270 | 64 | 27 | 15.9 | |
| 250 | 10 | D672-150LB | D672P150XLX10 | 236 | 230 | 201 | 325 | 71 | 28 | 20.6 | |
| 300 | 12 | D672-150LB | D672P150XLX12 | 282 | 259 | 240 | 375 | 81 | 33 | 23.8 | |
| 350 | 14 | D672-150LB | D672P150XLX14 | 314 | 295 | 277 | 413 | 92 | 41 | 28.7 | |
| 400 | 16 | D672-150LB | D672P150XLX16 | 362 | 355 | 329 | 470 | 102 | 41 | 33.5 | |
| 450 | 18 | D672-150LB | D672P150XLX18 | 413 | 356 | 340 | 533 | 114 | 41 | 35 | |
| 500 | 20 | D672-150LB | D672P150XLX20 | 455 | 377 | 387 | 584 | 127 | 41 | 41.4 | |
| 600 | 24 | D672-150LB | D672P150XLX24 | 548 | 490 | 467 | 692 | 154 | 51 | 51 | |
| 700 | 28 | D672-150LB | D672P150XLX28 | 682 | 570 | 552 | 799 | 165 | 50.8 | 50.8 | |
| 750 | 30 | D672-150LB | D672P150XLX30 | 702 | 570 | 557 | 863 | 167 | 50.8 | 50.8 | |
| 800 | 32 | D672-150LB | D672P150XLX32 | 702 | 570 | 557 | 905 | 191 | 50.8 | 50.8 | |
| 1200 | 48 | D672-150LB | D672P150XLX48 | 1168 | 841 | 805 | 1385 | 254 | 90 | 90 | |
| 50 | 2 | D672-300LB | D672P300XLX2 | 38 | 81.8 | 70 | 102 | 44 | 14 | 7 | |
| 65 | 2.5 | D672-300LB | D672P300XLX2.5 | 59 | 111.1 | 82.5 | 118 | 48 | 27 | 11.2 | |
| 80 | 3 | D672-300LB | D672P300XLX3 | 73 | 120.5 | 93 | 132 | 48 | 27 | 11.2 | |
| 100 | 4 | D672-300LB | D672P300XLX4 | 96 | 133.3 | 110 | 157 | 54 | 27 | 11.2 | |
| 125 | 5 | D672-300LB | D672P300XLX5 | 111 | 135 | 120 | 186 | 57 | 27 | 11.2 | |
| 150 | 6 | D672-300LB | D672P300XLX6 | 142 | 174 | 153 | 217 | 59 | 27 | 15.9 | |
| 200 | 8 | D672-300LB | D672P300XLX8 | 188 | 212 | 180 | 273 | 73 | 28 | 20.6 | |
| 250 | 10 | D672-300LB | D672P300XLX10 | 236 | 254 | 222 | 327 | 83 | 33 | 23.8 | |
| 300 | 12 | D672-300LB | D672P300XLX12 | 282 | 282 | 284 | 385 | 92 | 41 | 28.7 | |
| 350 | 14 | D672-300LB | D672P300XLX14 | 314 | 325 | 310 | 416 | 117 | 34.5 | 41.4 | |
| 400 | 16 | D672-300LB | D672P300XLX16 | 362 | 350 | 338 | 472 | 133 | 34.5 | 41.4 | |
| 450 | 18 | D672-300LB | D672P300XLX18 | 413 | 424 | 412 | 537 | 149 | 40 | 51 | |
| 500 | 20 | D672-300LB | D672P300XLX20 | 454 | 446 | 440 | 588 | 159 | 43 | 51 | |
| 600 | 24 | D672-300LB | D672P300XLX24 | 548 | 500 | 505 | 692 | 181 | 60 | 51 |
The double‑offset butterfly valve features compact structure, light weight, fast opening‑closing speed, easy installation and maintenance, together with excellent flow regulation and shut‑off performance. It can be equipped with single‑acting or double‑acting pneumatic actuators according to working conditions, with optional accessories including solenoid valves, limit switches, air filter‑regulators and positioners to realize remote automatic control. It is widely used in oil & gas, chemical, power, metallurgy, water treatment, paper‑making, HVAC and industrial process control industries.