Digital Vernier Interface with a PC 3

[NimChimpsky]

Hello All,

I need to record the continuous elongation of a bolt as torque is applied. I was planning on using an electronic digital vernier and connecting it to the pc similar to the below:

http://digital-caliper.co.uk/product_info.php?products_id=395

Does anyone have any experience of this? Or know of a cheaper equivalent product?

Thanks,

 

[MintJulep]

How do you plan to measure and record the torque with that caliper?

 

[redpicker]

I'm just curious what a "digital vernier" is.

The link describes a digital caliper with a PC interface. Where does the vernier part come in?

 

[NimChimpsky]

MintJulep, the torque will be measure with a torque wrench, the elongation is to be measured with calipers.

Redpicker, please read my post as "digital calipers with a PC interface", disregard the vernier aspect. I often refer to vernier gauges as calipers.


Thanks,

 

[CoryPad]

Continuous elongation of an externally threaded fastener usually is measured using strain gages or an ultrasonic transducer. Before and after length measurements with a micrometer, not a caliper, is common too. An alternative is to measure the clamping force instead of elongation using a force washer. I recommend looking at the following:

http://www.strainsert.com/products/custom-internally-gaged-bolts-and-studs/

http://www.mcrts.com/products/UltrasonicSensors/UTensorI.aspx

http://www.pcb.com/FasteningTechnology/ForceWasherTransducer

 

[MintJulep]

So how do you record the torque with a torque wrench?

If you want a torque vs. elongation curve you need to measure and record both.

If you want "continuously" then the measurements need to be recorded simultaneously.

If you only need discrete points then a pad of paper and a pencil work just as well as a PC interface.

 

[NimChimpsky]

Yes good point MintJulep.

Thanks for the information CoryPad. Some interesting bits of kit there.

 

[analogkid2digitalman]

MicroRidge makes interfaces for Mitutoyo and other manufacturer communications standards that serve as a USB-based standalone keyboard wedge- no software required.
Very convenient, I have deployed several within our company.

-AK2DM

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