Impact testing devices
Impact testing devices
(OP)
As the subject says, I'm looking for a device which can measure the impact force for me of a load that is connected to a chain that falls.
I've seen a few out there and was wondering which one you guys recommend. The load will be in the rance of 5-20 tons.
I've been coming across impact loading more and more in my work and decided its time I back up theory with actual test results.
One that gives the load would be nice. Acceleration and impact time are good as well however not essential as if you have the impact load you can design to the load.
It should be able to connect to a chain.
Preferably its usb and has a install and leave kind of deal so I can leave it in places for a day to get the maximum and average number of peak stresses.
Regards
I've seen a few out there and was wondering which one you guys recommend. The load will be in the rance of 5-20 tons.
I've been coming across impact loading more and more in my work and decided its time I back up theory with actual test results.
One that gives the load would be nice. Acceleration and impact time are good as well however not essential as if you have the impact load you can design to the load.
It should be able to connect to a chain.
Preferably its usb and has a install and leave kind of deal so I can leave it in places for a day to get the maximum and average number of peak stresses.
Regards





RE: Impact testing devices
Any idea what frequency range you need? or the impact time if you like?
I think you are looking for a load cell, 20 kN or so
I've used these guys in the past, they aren't the most expensive around
https://www.pcb.com/Products.aspx?m=1204-02A
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Impact testing devices
http://www.instron.com/en-us/testing-solutions/by-...
RE: Impact testing devices
Trying to test at impact rates with conventional testing machines is really difficult as to obtain high speeds is very expensive in terms of hydraulic systems and electromechanical machines will never be fast.
You need to consider Drop Weight machines fitted with suitable slack adapters and probably needing Piezzo Electric Load cells to obtain sufficient dynamic response to measure forces accurately at high rates.
20 Tonne machines would be huge and very, very costly
RE: Impact testing devices
Actually a quick image search for "20 ton spring scale" shows that digital models are available, and they probably have these features built in.
RE: Impact testing devices
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Impact testing devices
You might have to put several pieces of equipment together and do a little programming of a data collection/analysis program, but both are relatively easy. I've used such for dynamic structural analysis of amusement rides and industrial equipment.
RE: Impact testing devices
Strain gauging a link in the chain or a custom designed link with strain gauges are cheap solutions that will give good dynamic response.
je suis charlie
RE: Impact testing devices
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
[IMG http://tinyurl.com/7ofakss]
Need help writing a question or understanding a reply? forum1529: Translation Assistance for Engineers
Of course I can. I can do anything. I can do absolutely anything. I'm an expert!
There is a homework forum hosted by engineering.com: http://www.engineering.com/AskForum/aff/32.aspx
RE: Impact testing devices
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Impact testing devices
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
[IMG http://tinyurl.com/7ofakss]
Need help writing a question or understanding a reply? forum1529: Translation Assistance for Engineers
Of course I can. I can do anything. I can do absolutely anything. I'm an expert!
There is a homework forum hosted by engineering.com: http://www.engineering.com/AskForum/aff/32.aspx
RE: Impact testing devices
je suis charlie
RE: Impact testing devices
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
[IMG http://tinyurl.com/7ofakss]
Need help writing a question or understanding a reply? forum1529: Translation Assistance for Engineers
Of course I can. I can do anything. I can do absolutely anything. I'm an expert!
There is a homework forum hosted by engineering.com: http://www.engineering.com/AskForum/aff/32.aspx
RE: Impact testing devices
Otherwise on a force hammer for modal work we'd just use a hammer with an accelerometer, whereas the force gage is also essential.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Impact testing devices
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
[IMG http://tinyurl.com/7ofakss]
Need help writing a question or understanding a reply? forum1529: Translation Assistance for Engineers
Of course I can. I can do anything. I can do absolutely anything. I'm an expert!
There is a homework forum hosted by engineering.com: http://www.engineering.com/AskForum/aff/32.aspx
RE: Impact testing devices
Absolutely no comparison. Something that looks like a rigid structure - say a 1m x 1m x 0.05m steel plate with chain and accelerometer attached to the centre of a 1 x 1 face - will produce a peak acceleration way in excess of the peak force divided by the mass. The peak force under impact loading is not accelerating the entire mass uniformly. Only the section attached to the chain is experiencing the peak acceleration.
OTOH the spring balance will measure the peak force (and infer acceleration) accurately, but the system is much more compliant and the peak force much lower than the chain with no spring balance.
je suis charlie
RE: Impact testing devices
It became clear that a piezoelectric force sensor was the way to go. They are very fast and can capture the force v time for highly dynamic events. You can in most cases configure the data collection system to buffer a bit of time and trigger the saving of data to disk, if you want to capture an event automatically and ignore extraneous data.
This type of system isn't cheap but if you want the data free of inertial influences, probably one of the best.