Pneumatic Diversity Vent
The Aperture Science Pneumatic Diversity Vent is the primary component of the tubes in the Portal series. Although the component itself was not present in the first Portal, this component is the only means of supplying pneumatic pressures to push products throughout the Aperture Science computer-aided Enrichment Center, and opposite to the Vital Apparatus Vent.
As the second part of its name suggests, the Pneumatic Diversity Vent's purpose is also to redirect various products to a different location of the Enrichment Center if it were needed there.
The pneumatic pressures providing the suctions in the tubes have existed since Portal, and has remained prevalent throughout Portal 2. The Pneumatic Diversity Vents are the source of the powerful vacuums in tubes, and will therefore suck up any object(s) near it to provide continuous transportation if other Pneumatic Diversity Vent components are nearby. It is never demonstrated just how powerful the suction truly is in Portal 2, however in an early E3 2010 footage when the components were a testing mechanic, these components were originally able to remove various panels from their positions.
These components have transported a wide range of Aperture products such as Cubes (including Weighted Cubes and Edgeless Cubes), Turrets, elevators from a Chamberlock-specific Tube network (straight direction Tubes only), and other such objects to various locations they are needed.
There have been cases where Chell boards tubes to be transported with the help of the pneumatic pressures. In Portal, after Chell escapes from the testing track, she boards a damaged tube, but is unexpectedly pulled back into Test Chamber 09 by GLaDOS. In Portal 2, she uses it again in a Tube riding scene in Chapter 5 in which both Chell and Wheatley are sucked up through the vents via pneumatic pulls and rapidly travel around the facility. Although this was not a part of Wheatley's plans to confront GLaDOS, he realizes that the pneumatic pulls can bring them to Her.
As part of the Peer Review DLC for Portal 2, the Pneumatic Diversity Vents also serves as an entrance to the extra courses found in the Hub.
GLaDOS appears to be the only source of operating the pneumatic pulls in the tubes. Her power over these Vents is demonstrated in Portal 2, in a catwalk scene where the Oracle Turret is first found; unveiling entire tubes to have been completely non-functional after the destruction of GLaDOS.
- According to unused skins for the screens, the vents would've been capable of carrying Weighted Companion Cubes, open fire turrets, Hover Turrets and various tables and chairs that are present in observation decks.