Vented Screws are also known as Vacuum Screws, Ventilation Screws, or Hollow Screws. A vented screw features a hollow core (has a hole drilled through it) and are specially designed to allow the release of gases, contaminants, and pressure through the fastener.
Vented screws are ideal for use in high vacuum (UV) and ultra high vacuum (UHV) equipment, as well as other high pressure environments and applications where gas pockets can form. Center vented screws have a center bore drilled through their axis from the head through the threaded shank of the screw. This feature provides an outlet for the complete evacuation of trapped air and gas contaminants to be pumped away from blind-tapped screw holes, bottoms, sides and shoulders. In addition to vented screws, washers with vent grooves can be made to ensure the venting of the cavity found under the screw head.