Noise from gear Reducer
Noise from gear Reducer
(OP)
Wondering why I have three of four Tigear2 right angle reducers driving conveyor that are much louder than one of them. One is about 72db the other three are 85 db. They are all new within 1 month old and are all driving the same type of conveyor.





RE: Noise from gear Reducer
Look for differences in couplings and is mounting arrangements and availability of acoustic radiating surfaces.
Check the lubricant levels in the gearboxes.
Mike Halloran
Pembroke Pines, FL, USA
RE: Noise from gear Reducer
RE: Noise from gear Reducer
Or possibly the quiet box is the aberration and the noisy boxes are the norm.
RE: Noise from gear Reducer
Look for an asymmetry in loads, as reflected in motor currents or motor speeds, if you have a good tachometer.
Either the quiet one is underloaded, or the noisy ones are overloaded, or if you are lucky, optimally loaded.
You may find a clue in the design/selection documents, if you can access them.
Mike Halloran
Pembroke Pines, FL, USA
RE: Noise from gear Reducer
RE: Noise from gear Reducer
Second - What Halloran and TB. say.
Third - contact Dodge engineering to see if they know of conditions that cause these reducers to be loud
Baldor-Dodge Product Technical Support: phone: 864-284-5700 fax: 864-281-2317 brgpttechsupport@baldor.com
The guys at BD Tech support should have a backlog of thousands to tens of thousands of problem reports to go on.
I am reminded of a system that had the gear drive replaced with a belt drive to remove an obnoxious amount of noise. The result was no noticeable change in the noise. Turns out it was the PWM to the drive motor. An FFT showed the main contributor frequency, and an EE confirmed it as the PWM frequency.
RE: Noise from gear Reducer
RE: Noise from gear Reducer
If there is available to bring some radial load from conveyor shaft to the reducers bearings it could be the main reason of the noise that also belongs from belt tension and coveyor load.
RE: Noise from gear Reducer
RE: Noise from gear Reducer
Usually when diagnosing these types of problems, a good first step is to verify the components are installed/assembled correctly. I took a quick look at the installation instructions for this type of gear reducer and there are a couple things you should check, the most obvious being correct installation of the motor shaft coupling.
Regarding your last comment about excess radial load on the output shaft from timing belt tension, this would likely only cause abnormal noise/vibration if it produced damage to the output shaft bearings. The tapered roller bearings on the output shaft are installed and preloaded at the factory, and the unit is sealed after being filled with lubricant. The only reason tapered roller bearings would produce the level of noise you describe is if they had suffered serious pitting/spalling damage. The easiest way to check for this type of bearing damage is to test a sample of the lube oil for ferrous metallic debris.
Good luck with your problem. And please post again when you determine the cause of the problem and how you finally resolve it. It might prove helpful to someone else in the future.
Terry
RE: Noise from gear Reducer
that wouldn't happen to be the frequency of what you are hearing, is it?
RE: Noise from gear Reducer
RE: Noise from gear Reducer
10 minutes work with a PC microphone and free FF software would likely make it quite clear IF the "noise" is a tone, and IF the frequency of the tone is shaft rpm X sprocket tooth count ( either shaft would be the same).
http://www.cns.nyu.edu/~david/courses/perception/l...
The FIRST think I'd do is identify the frequency content of the "noise." Without that, I'd be guessing about any cause and effect, which makes a solution a big old guessing game.
The variation in noise level/loudness between "identical" machines can sometimes be attributed to stuff like reflection and reverberation and other "room effects."
RE: Noise from gear Reducer
http://www.pfeiferindustries.com/troubleshooting/t...
RE: Noise from gear Reducer
You might also double check that you are using the correct type of belt for the sprockets. Every manufacturer makes different proprietary types of timing belts that each require sprockets with a specific matching groove profile. They can appear very similar and it would be very difficult to determine if you had the correct combination of belt and sprocket just by looking at them. Hopefully there are part numbers on the belt and sprockets.
RE: Noise from gear Reducer
I hope the OP gets some real info about his noise problem rather than making big decisions based on my synchronous belt comments.
//If// he can determine the noise is being radiated from the flat walls of the gear housings, or the frequency of the noise is NOT belt tooth mesh, then another approach should be taken.
"Noise generation from synchronous belt drive systems has been an on-going issue in the
Industrial Power Transmission Market. " But then the report makes a bunch of comparisons ( 10dBA lower, etc) without once mentioning how loud they are.
https://www.google.com/url?sa=t&rct=j&q=&a...
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Looks like his drives are max 28 HP, and maybe much less.
http://www.baldor.com/support/Literature/Load.ashx...
We sold a bunch of variable speed 50 HP big torque belt driven machine tool spindles. The straight tooth synchronous belt drive (with sprockets over 3 inches wide from memory) came right out of the engineering department of one of the big belt manufacturers. The belt noise level at higher rpms was so loud ( I seem to recall over OSHA standards) and annoying they fabricated enclosures to try and knock it down, which brought on a series of other problems, among which was violating belt drive requirements for ventilation.
The Goodyear herringbone timing belt brochure proudly makes this claim.
"Up to 19dB quieter than straight tooth belts"
http://www.goodyearep.com/productsdetail.aspx?id=3...
Quieter ain't the same as quiet, so I believe what is implied about the other guys' drives and even their own is worth noting.
http://gatesbeltsandapplications.blogspot.com/2010...
In the above Gates link they kind of pussy-foot around the noise issue in any quantitative way.
little teeth pump small amounts of air. The various profiles of automotive timing belts running on 1 inch wide sprockets in enclosed cases are not easily compared to
Large teeth on industrial size drives pump big puffs of air. A teeny groove or 20 thou of tip clearance is not going to change that materially.
If the tooth mesh frequency happens to be around 1000 - 3000 Hz (1000 rpm and 60 teeth, 1800 rpm and 33 teeth, etc) then the siren tone will sound even louder.
http://read.uconn.edu/PSYC3501/Lecture12/audiogram...
A mosquito's ~ 600 Hz buzz isn't very loud. But because it is ~ a tone, and in the sensitive valley around 1000 Hz, it quite audible and attention getting.
http://hypertextbook.com/facts/2000/DianaLeung.sht...