SMC Corporation VHS20-02B Vacuum Ejector Unit

SMC VHS20-02B is a 3-port, 2-position pneumatic relief valve in the VHS20 family designed to vent residual pressure in pneumatic lines and prevent unintended starts during maintenance through a padlock‑able exhaust position. It features a 20 (ACG20) body size with Rc 1/4 port size, a handle/bonnet made of aluminum (option B), and an exhaust port option that can include a built‑in silencer (S). The unit is rated for +1.5 MPa proof pressure and conforms to OSHA standards for residual‑pressure relief valves with locking holes. Operation uses a two‑step action—push the handle and then rotate—to avoid accidental actuation. Variants exist, including VHS20-02B-S and VHS20-02B-BS with built‑in silencers, and suffixes such as R‑D (e.g., VHS20-02-B-R-D) for mounting configurations, as listed in SMC catalogs. This valve is typically used in pneumatic tooling, automation cells, grippers, and fixtures where controlled relief of residual pressure is required when servicing equipment or re‑pressurizing systems.