Hey!
I hope this isn't a duplette, but I haven't found an answer so far.
As a university project we have to construct a tensile testing machine (Tensile testing - Wikipedia). We want to measure the elongation and the applied force with sensors controlled by an arduino.
But we are still not sure how to measure big forces. Our probes are likely to break somewhere at 10kN.
Does anyone of you have a good idea?
Thank you very much,
Sammy
As far as know, all those things are measured with load cells (strain gauge).
Buying a load cell of 10kN is no problem. Industrial load cells of 10kN are few hundred dollars up to a few thousands dollars, I don't know if there are cheap load cells of 10kN.
I think it is easier if the load cell is compressed. Is that mechanical possible ? Perhaps four load cells can be used. In a bathroom scale, often 4 load cells in the corners are used and the weight of all four are added.
Somewhere near 10kN ? Perhaps you should buy a load cell of 100kN ? To be sure that it can be measured.
Hey, thanks for the quick reply.
I found load cells as well, but it seems as if the are too expensive for our project. We have to stay low budget :-/
I thought of using a kind of spring scale, where the spring constant is known and I could measure the elongation of that spring. But I'm not sure if this is going to lead to sufficient exact results.
The spring between the item-to-test and the pulling part ? If the item breaks, the collapsing spring will be very dangerous.
A load cell of 1000kg is about 50 dollars on Ebay.
AliExpress has 500kg load sensors of 30 dollars each.
We have to stay low budget
This is very dangerous and extremely foolish for a project dealing with 10 kN forces.
How are you generating tensile force?
You are totally right with the spring. We won't use that.
The task includes, that the tensile force should only be generated in a mechanical way and by hand.
Therefore we plan to use a car jack.
jremington:
This is very dangerous and extremely foolish for a project dealing with 10 kN forces.
I agree - that's a lot of force, danger to life and limb - so unless you are just adding sensors to an
existing certified rig I can't see this being a sensible project.
You are all right. I don't like the idea of applying such great forces as well.
But it's the order from our university. We will talk to the teachers on tuesday maybe they will see the point.
Thanks for all the replies.