I’m often asked by clients what are the advantages of using an IRD ‘soft bearing’ balancing machine, instead of using a ‘hard bearing’ balancing machine.
Both types of balancing machine are capable of dynamically balancing a work piece rotor. The term ‘hard bearing’ is used to describe different types of balancing machines.
For example, on a CEMB rigid type of balancing machine, the work supports are rigid and all the unbalance forces are absorbed through a piezo-type pickup. On this type of balancing machine, it can be installed on any solid type of floor capable of supporting the weight and the rotor being balanced.
Whilst on another, the Schenck semi-rigid type, the work supports are semi-rigid, and the movement of the work support is measured with a velocity type transducer which is the same as a soft bearing machine. The base of the machine must also be installed on an isolated concrete foundation, for maximum machine sensitivity.
The installation for an IRD soft bearing balancing machine, however, is unique in that IRD specialise in portable balancing machines from less than 1kg table top machines, right up to 300-tonne low-speed turbine balancing machines transported around power plants to avoid turbine shipping costs.
I recently wrote a detailed blog post about how an IRD balancing machine can improve workshop productivity – read about it here.
When it comes to the main advantages of using an IRD soft bearing balancing machine, they are:
The IRD soft bearing system is linear, meaning that regardless of speed, the amount of displacement measured does not change. This enables excellent low-speed balancing results within tolerance at the service speed.
There is direct measurement and display of the Mass Centre Displacement of the rotating centre line in Microns or Mils. This is advantageous when balancing first critical Flexible rotors, whilst there are also applications such as scroll balancing where this is projected and the flex corrected for at low speeds.
Another advantage with an IRD soft bearing balancing machine is that minimal foundations are required due to the low system forces generated, the pendulum, ‘low friction design’ achieves this by measuring Displacement of the rotating centre line rather than force. No base is therefore needed to absorb the force and provide a differential movement reference on the pedestal. This means the balancing machine can be portable.
IRD balancing soft bearing anti-friction assemblies have a unique design that allows the work support rollers to have a flat surface, as opposed to crowned rollers on hard bearing systems. The significantly reduces the risk of damage to the client’s rotor journals.
A further advantage with the IRD soft bearing system is that the instruments have always effectively applied the ISO 1940 tolerances, by being able to calculate the rotor centre of gravity. This is something that heard bearing balancing machines cannot do.
Finally, the latest IRD 295+ flagship system is also now equipped with the option to use the new ISO tolerance standard 21940-11:2016.
If you’d like to find out more about how our IRD soft bearing balancing machine system can give you competitive advantage, please get in touch here and mention this Blog post.