AccuGroup's Vented Screws, also called Vacuum Screws, Ventilation Screws, or simply Hollow Screws, feature a hollow core, and are specially designed to allow the release of gases and pressure through the middle of the fastener. Vented Screws are widely used within vacuums. These components allow surface contaminants to be extracted from blind-tapped holes, and can also prevent pockets of gas from becoming trapped at the base of blind drilled holes, which can cause virtual leaks within vacuums.
A virtual leak is a trapped volume of gas within a vacuum chamber - in this case, trapped at the tip of the screw. Virtual leaks can cause problems during the depressurisation process, producing incorrect readings, and increasing the time taken to achieve an optimal level of pressure. After depressurisation, these problems continue - residual trapped gas is slowly released into the vacuum chamber by travelling along the threads of the screw. This causes a vacuum to gain pressure over time, giving the false appearance of a leak.
Vented Screws are specifically designed to combat this issue. The central cavity (or vent) of a Vented Cap Head Screw allows pressure to transition freely from the nose of the screw into the vacuum chamber - this prevents hidden pockets of air, speeding up the pump-down process, and allowing the vacuum chamber to remain accurately depressurised for a greater length of time.
Vented Screws are manufactured to order. If you require imperial measurements, or do not see the exact size you require listed on our online store, please contact us - it is likely that we can offer the dimensions you require.
Bespoke Vented Screws Manufacture
High precision, bespoke manufacture of Vented Screws to customer specification. State of the art facilities specialising in both small batch prototyping and large scale manufacture.