When should the rotary valve housings have vent holes ?
The inclusion of vent holes or ports in rotary valve housings is a specific design feature, not a universal standard. Their presence depends entirely on the application and the type of rotary valve in use.
Here's a breakdown of when they are typically recommended and when they are not:
| Scenario | Recommendation & Purpose |
|---|
| For fine/poorly-flowing powders | Recommended. Vent ports help release trapped air, prevent material fluidization, and improve product flow . |
| In pneumatic conveying systems | Recommended. They are crucial for pressure equalization, preventing pressure buildup that can disrupt smooth material flow between different pressure zones . |
| For dust control & cleaner operation | Recommended. Vent ports allow excess air or gas carrying fine particles to escape, reducing dust emissions . |
| When high sealing is critical | Not recommended. Vent holes are unsuitable for explosion isolation, vacuum systems, or any scenario requiring strict dust-tight containment. |
| In hygienic applications | Not recommended. In food, pharma, or chemical processing where avoiding contamination is paramount, vents can be a point of ingress and are typically avoided . |
| Handling toxic/hazardous materials | Not recommended. Vents could potentially allow the release of dangerous substances into the environment. |
