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Vibration figures and removing the uncertainty
Rank: New forum user
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If an individual tool is tested for its true vibration figure can the uncertainty figure +/- 20% be removed and exposure limits just be based on the test on that individual tool?
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Rank: Super forum user
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Like an MOT - only valid for the date and time of test in its presented condition
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Rank: Super forum user
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Like an MOT - only valid for the date and time of test in its presented condition
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Rank: New forum user
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I was led to believe the figures quoted are bench test figure only offered by manufacturers at the point of test. The variants in tool performance has been calculated to fall within the publised tolerances. This is because tool vibration resultts vary due to construction variables and test peramiters. If a true test of a tools vibration is required then a direct test would be needed. Again this will alter due too tool fatigue over its lifespan and operator handling. The offered results should be used a a guide at best. Hope this helps? Steph
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Rank: New forum user
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Thank you, that answers my question :-)
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Rank: Forum user
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Have you considered testing the actual vibration through the hand? There are major differences from individual to individual? havSense is a tool which measures the vibration through the hand and is used by the operative in the hand. Speak with Keith Phillips - email: keith.phillips@laplace.co.uk who's system is very good and reasonbly priced. Remember, figures provided already provide a degree (usually 1.5m/s2) of uncertainty, which can be signficant, thats not forgetting damage, wear and tear etc. and general degradation - which utlimately increases vibration potential.
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1 user thanked Waz for this useful post.
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Rank: Super forum user
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Where are you getting "vibration uncertainty figure +/- 20%" from ? This does not sound like it is from Manf data so where is it from ? I suspect people may be able to give better answers if this is known. Chris
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Rank: Forum user
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The published figures are not reliable as there are a lot of things that affect the vibration value of the tool in question, for example:
The electricity supply. If this is via an onsite transformer with other things plugged into it as well then you get a significant voltage drop which ultimately affects its vibration value. If this is then being used with a very long lead then you will also have a significant voltage drop from that, exacerbating the problem.
The age of the tool. As tools get older they have higher vibration values due to wear in bearings, gears and motors.
The use of the tool. An angle gringer for instance has a higher value if it being used for grinding metal than with a sanding disc and higher still if used for cutting concrete.
You can use meters that attach to the tool to get a much more accurate measure but far better to measure the user.
Edited by user 11 August 2018 23:20:49(UTC)
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Vibration figures and removing the uncertainty
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