Hello All,
I am trying to identify what is an acceptable level of seismic ground vibration that will not impact the performance or product quality from our machine tools.
We are looking into moving some machines in our facility; however, the proposed location will put the machines in a part of our build that is close to a railway line that runs by our facility.
The machines in question are mostly manual engine lathes and knee mills, but also a small Haas vertical mill and a surface grinder.
I am planning to have a ground vibration study performed to assess the differences between the two different locations, but currently I am unable to identify what is an acceptable level, or industry standard, for ground/seismic vibrations related to the machines mentioned above.
Does anyone know of a reference where I might find this information?
Thanks for any input
Jonathan
@Jonathan Horrobin
I have used “Vibration Criterion (VC) curves” in the past. Web search that term, though I'm not sure it will help your particular question. My application was more precision equipment that fell into VC-B.
Jim
I don’t have any direct info on where you can find the info you are looking for, but hopefully this insight helps a little;
Most newer quality machines will have a movement or vibration sensor on them that will disable them. It is gps based if I remember correctly. The intention is so if you move the machine without the manufacturer knowing, they have a claim against warranty work. They will tell you it is for theft and seismic conditions though. I am unsure if Haas has this technology, but you could ask them.
For the manual mill and lathe, the trains near by wont have any measurable effect. Just tell who ever is running them not so make a cut when they can feel the train.
As far as the Haas and the surface grinder, they will definitely feel the impact of the trains near by. I had a high precision part I was trying to inspect, and I had to time my CMM runs based on when semi-truck traffic 2 miles down the road was minimal so my readings wouldn't be affected. I would see between .0015" and .003" of CMM deflection when a truck was driving by.
To mitigate this, it would be standard practice to pour a cement isolation pad for each the surface grinder and the Haas. I would recommend a 6-8" thick floating pad for each machine.
I hope this helps. Happy to elaborate more or answer any other questions you might have.