Avoid basic errors in setting up and running vacuum boost, says supplier

Even small mistakes in the setup and operation of vacuum boosters can lead to costly downtime or serious damage, says vacuum specialist Busch Group.

The supplier has come up with a list of the six most common mistakes relating to vacuum booster systems – and points out how to avoid them.

1. Not allowing cooling time before reaching ultimate pressure. The company always recommends allowing a vacuum booster to cool down between running at maximum differential pressure and ultimate pressure. Maximum differential pressure occurs during the evacuation cycle and generates the most heat. 
2.  Ambient temperature fluctuations. Sudden strong reductions in the ambient temperature during operation, especially at ultimate pressure, can be critical to a booster. The thermal shock causes the housing to contract while the lobes are still hot, with the potential outcome that the vacuum booster seizes. A suddenly-opened door in colder months, for instance, can have this type of effect.
   
   
3. Allowing sudden fluid inrush. Fluid inrush is a risk in processes that involve condensable vapours, wet gases, liquid transfer or thermal cycling. This includes applications such as vacuum distillation and vapour recovery. This sudden fluid inrush can have the same effect as air temperature reductions, causing abrupt cooling and ultimately damaging the booster.
   
   
4. Incorrect ratio between booster and backing pump. In applications where cycle times are just a few seconds, the operator must ensure that the staging ratio (the ratio of the vacuum booster pumping speed compared to that of the backing pump) is small – for instance, 2:1. Higher staging ratios are possible, but at the expense of cycle time.
   
   
5. Allowing dust and debris to accumulate. This is clearly more of an issue in certain industrial processes. Where the problem arises, Busch recommends installing dust filters on the inlet side to protect both the vacuum booster and the downstream vacuum pump.
   
   
6. Not ensuring leak tightness when handling critical gases. Again, this is likely to be an issue only in specific processes where costly pure gases, such as helium-3 or helium-4, where any exchange with the ambient air must be avoided. 

Understanding these common mistakes and implementing the recommended practices will not only enhance the performance of the vacuum booster, says Busch, but also contribute to safer and more economical industrial processes.

01952 677432 
www.busch.co.uk