I. Core Role

1. Under static conditions, it presses against the valve seat to block the compressed‑air passage and provide sealing.

2. When a pulse signal triggers pilot‑port relief, pressure inside the upper diaphragm chamber drops. The cross‑diaphragm pressure difference lifts the diaphragm, opening the air‑path and releasing instantaneous high‑pressure blast air into the blow tube for filter‑bag cleaning.

3. When the pulse signal ends, the upper‑chamber re‑pressurizes; the diaphragm resets and closes to terminate jet‑blowing.

4. It also provides gas‑path buffering and isolation to prevent cross‑gas leakage. The diaphragm directly determines pulse‑valve response speed, jet‑blowing force and service life.

II. Structural Form

Available in single‑layer and double‑layer construction (main diaphragm plus auxiliary sub‑diaphragm). Double‑layer diaphragms are the mainstream option for dust‑removal pulse‑jet valves.

III. Commonly Used Materials

Nitrile rubber (NBR): Good resistance to compressed air, wear‑resistant and cost‑effective.