Sealing device for openings in oil tanks - is operated only by special tool to avoid unauthorised emissions

摘要

The device for sealing an opening on oil tanks has a self-sealing closure member (2) attachable to the bottom (1) of the tank or other container so as to seal the medium from the atmosphere. The seal can only be broken by using a special tool. The closure member is pref. cylindrical having inside in the centre a downwardly conical shaped attachment (4) on which sits a truncated cone (6) which is loaded by a compression spring (15). Underneath the attachment there is a bore (5) with an internal thread into which the special tool can be inserted. ADVANTAGE - Uncontrolled emissions of oil are prevented and the device is reusable over long periods of time.