In the animation above, the red circle represents an imbalance, the red arrow represents the force exerted due to centrifugal forces. The green circle represents a correction mass and the green arrow represents the counter-force exerted by this mass to cancel the imbalance force out. This is a very simple representation of a static (single plane) imbalance.
What is 'In-situ Balancing'?
In-situ (or on-site) balancing is a form of rotational balancing which is achieved on site. Similar to car tyre balancing however on an industrial scale, most impellers/rotors will develop imbalance due to many factors; some unavoidable. It can be detected using Vibration Analysis. In static imbalance, there is a single heavy spot in the unit which generates an imbalance force; by applying a balance force in the opposite direction, the two forces cancel out leaving the unit neutral and free of imbalance.
Coupled imbalance can occur with larger plane distance (long rotors for example), this is where there are two static spots on opposite planes are creating the imbalance forces. This can be described as a 'twist' in the unit balance. A combination of both coupled and static is where the opposite planes are out of sync and one side is also heavier than the other, this is called Dynamic Imbalance.
What are the benefits of 'In-situ Balancing'?
Reduce maintenance costs - Imbalance is a large factor in reducing the lifespan of bearings and other mechanical components, therefore by balancing machinery, these components last longer.
Reduced energy costs - units running out of balance generally consume more power as the driver must work harder to compensate, balancing will reduce overall energy costs.
Noise/vibration reductions - Imbalance causes higher vibration and noise levels which can be greatly reduced once a unit is balanced.
No removal required - The unit does not need to be stripped and removed for in-situ balancing, reducing the repair cost of some machinery. However, not all dynamic imbalance can be rectified on-site due to physical restrictions; some may require a Workshop Balance.
Why choose PFE Limited for your 'In-situ Balancing?
We have an extensive knowledge and enthusiastic drive when it comes to our work, we will always go the extra mile to ensure our service is the best service we can possibly provide.
PFE offer tailor-made reporting for every client, every part of the report can be modified to suit your needs and/or requirements, we are proud of our in-depth balancing reports and we are sure you will be happy with our reporting standard.
With competitive pricing and an unrivalled quality of service, PFE Limited will meet your balancing needs.
How we do 'In-situ Balancing'
In-situ Balancing involves PFE Limited temporarily attaching tachometer and vibration transducers, which may involve the occasional removal of a shaft guard. From this point, the unit must run for initial readings and stop for the addition of trial weights & trim weights until the unit is balanced. It may require quite a few runs of the unit depending if reaction is high enough. All health and safety procedures including locking between runs will be performed.
Once balanced, a report will be sent via email showing initial and final imbalance readings and any comments on the remaining vibration of the machine. It will also include any recommendations on how to further improve the quality of the running of that machine.