| 摘要 |
A humidifier unit (10) for injecting steam into air-conditioning ducting comprising at least one tubular portion (12) formed with at least one aperture (16) to enable steam to pass from the interior of the tubular portion (12) to the exterior thereof. The aperture (16) is formed through a wall portion (20) of the tubular portion to create an inwardly directed annular protuberance (18), which is integral with the surrounding wall portion (20). The protuberance (18) thus comprises the same material as the surrounding wall portion (20). Also a method of making such a humidifier unit (10) using thermal drilling or punching to create the aperture (16) and the annular protuberance (18). |
