Archive for June 2016

You Asked: Frequency of Cross Section Analysis

A customer asked this question during a crimp training session I was performing: What Frequency should you perform Cross Section Analysis on a specific wire and terminal combination?

I will provide a response to this question shortly.  But you need to understand the uses of Cross Section Analysis. And how it applies go the crimping process in general and specifically how it applies to your company.

For those who are new to this technology, a crimp cross section is an image of the inside of a terminated wire. This image shows the result of how the five elements of the terminal crimp process come together.  Valuable information can be pulled from this image. For a more detailed explanation, please read our post Terminal Cross Sectioning: Taking a Peek Inside.

I consider Cross Section Analysis as the Swiss Army Knife of Crimp Quality.  A Cross Section can serve many purposes. First as a base line master image of your crimp process in the initial production phase. This is a report that can be retained for future analysis or provided to a customer for their quality audit purposes.

Second, knowing the basic crimp configuration will provide an indication of how the crimp will perform. If the wire and terminal combination are specified and the crimp height is established by the terminal supplier then what you see in the cross section image is generally how the crimp will look through the crimp process. If the crimp wings are touching (or close to touching) the internal crimp walls or floor, this can cause crimp monitor alarms. Or if crimp wings are forming but not capturing stranding (uneven distribution), this is a sign the crimp could perform poorly in electrical testing or in use in the device it is installed into.

cross section (110)

Crimp Wings Touching the floor of the crimp.

cross section (130)

Under Compressed Crimp

Next, in process validation. Comparing the current image to the master image previously captured. Checking to see if crimp tool wear or other inconsistencies have caused the crimp profile to change.

Finally as a process improvement tool. When crimp elements come together, the process capability is the sum of these elements. Improving any of the elements (press, applicator, wire, terminal, operator/automation system) can improve the overall process. And that results in a better terminated wire.

So coming back to the frequency of cross section analysis, an initial image is important as a base line review of the crimp profile. Where there are crimp problems (crimp monitor “false alarms, customer complaints etc..) a crimp cross section helps to determine in process issues. This would be done on an as needed basis. In process image capture to compare the current image with the master image would depend on the overall volume of that crimp. Also consider any changes in the elements of the crimp process. For example crimp tool changes or wear or an introduction of a new wire supplier. Even as simple as an applicator removal and re installation at a later date can be a factor in variation.

There are no established guidelines on the frequency of cross section analysis other than what a customer may establish. But the use of cross section analysis as a validation, in process inspection and process improvement tool will only increase in the future. And why not? The information from this analysis can lead to a better quality electrical connection and a lower risk of failed electrical circuits from faulty electrical connections.

Global Technology Partners of WireProcess are industry experts in their areas of support to the wire processing industry. C&S Technologies are globally recognized for their expertise in crimp quality. For more information, visit our C&S site and our Cross Section Services page. Connect Your Way to WPS.