What size test rods should be used for testing metal detectors?

Respected members,

I need information about testing of metal detector for confectionery products. I have 3 test rods for testing of metal detector.

Ferrous:2mm

non Ferrous:3mm

stainless steel:5mm

 But i am still facing metal complaints from customer. Kindly advised me which sized test rods i should use for testing of metal detector.

Hi,

1, confectionery products, This is an international forum, and we may not know the name very well.

Generally speaking, this should be a product that is easy to detect, and there is usually no product effect.

Of course, I can't fully confirm. if possible, you can post a few photos of the product.

2, Do you have a picture of the machine? Because I want to know the specific situation of the machine.

3, The sensitivity of the machine is not directly related to the test rod size.

Even for test rods of the same size, the sensitivity may vary greatly.

So further, I want to know what signal value is your product and test rod respectively?

4, because even for test rods of the same size, the sensitivity may vary greatly.

Therefore, you need to ask local professional engineers to increase the sensitivity of MD as much as possible.

This of course includes the lowest possible interference including product effects.

5, If your MD hole size is too large, then you may also need to change to a smaller size.

So I also want to see your machine photos.

6, Do you have photos of metal contaminants complained by customers?

Of course, this is not important. MD has 2 most important aspects:

6.1, The highest possible sensitivity. ( Of course stability must be considered.)

6.2, An almost absolutely reliable rejection system. ( This is also actually a complicated topic. )

So, this is not a simple question.

If you can directly respond to the above questions, I will continue to answer / help.

Thanks.

Please fin picture.

Please fin picture.

It seems that the hole is not very large, so the sensitivity may not be high enough.

What is the size of this hole?

And, your machine does not seem to reject confirmation.

This is a photoelectric switch, used to confirm that it has been rejected by the machine.

In other words, there is a possibility that your machine has actually detected metal contaminants, but has not been reliably rejected.

This requires you to confirm on your machine, so you need to find the metal contaminants complained of for further testing and confirmation.

sorry, this is indeed a more complicated issue.

I also need feedback on several other questions. thanks,

I recommend you reach out to your metal detector manufacturer.  They can provide good insight and can also dispatch a technician to you.  If you are seeing customer complaints, the service visit from the tech is definitely worth the cost especially if you can have some key people work closely with the technician to learn from him / her.

Respected members,

 

I need information about testing of metal detector for confectionery products .I have 3 test rods for testing of metal detector.

Ferrous:2mm

non Ferrous:3mm

stainless steel:5mm

 But i am still facing metal complaints from customer.Kindly advised me which sized test rods i should use for testing of metal detector.

Ryan's suggestion is a good one in case machine is not correctly set up.

How do you validate the sensitivity with the test pieces ? How often ?

What is the specific complaint ?

What is height of package ?

I remember calling in a rep from a metal detector company, what a great education.  Somewhere along the line of this business a new person was put into the QA spot and she changed the metal detector program around and while things were passing just fine thru the detector they had never done a density check nor had a rep come in and check things out.

What was happening was that customers kept on complaining about metal inclusion.

The super experienced rep comes in, grabs their product, does a density check and finds the right samples that should be in use which were completely counter to what the HR person turned into a QA person was using.

Boom!!! problem corrected and the facility hired a real QA manager too.

Those reps are worth it - bring one in.

I remember calling in a rep from a metal detector company, what a great education.  Somewhere along the line of this business a new person was put into the QA spot and she changed the metal detector program around and while things were passing just fine thru the detector they had never done a density check nor had a rep come in and check things out.

 

What was happening was that customers kept on complaining about metal inclusion.

 

The super experienced rep comes in, grabs their product, does a density check and finds the right samples that should be in use which were completely counter to what the HR person turned into a QA person was using.

 

Boom!!! problem corrected and the facility hired a real QA manager too.

 

Those reps are worth it - bring one in.

What do you mean by "density check" here? Does it mean to verify metal detectors with Fe, NFe, SS every hour? Thanks.

First of all, I would check :

1- whether you actually have product ejections - outside of the tests -, and if you extract the contaminant from the ejected products : what are they? Even a metal detector cannot detect everything, you might need to suppress them at the source

2- how sure you are that the products that have been ejected cannot come back (as in, be put back) into the production flow

And then go deeper into the technical side. If your foreign bodies are not detectable / hardly detectable and/or the process is not 100% reliable, changing the settings of the detector will not help with your customer complaints.

Density check is tying in the specific product(s) to the metal detector settings.  Different products exhibit different readings of the metal detector.  That's why, typically a metal detector is set to a specific product.  When you change products you should change the metal detector settings.  The reason in doing this is to establish detection limits for each product as there will be some variations depending on the product.

Your test pieces for the detector should be the smallest sizes the detector can detect at the most sensitive setting.

What do you mean by "density check" here? Does it mean to verify metal detectors with Fe, NFe, SS every hour? Thanks.