Hello
I have a drum coil inductor that it's ferrite is broken.
It is related to a computer PSU and part number is unknown.
Can I glue its ferrite or use with this condition.
thank you

 

Most likely it's not going to have the same value as it did originally, but you can put it together and see if it's close enough to work, assuming it's not a mission critical computer. Also be sure to check for shorts. That thing looks like it has been through some abuse and if the insulator got scraped off of the copper it might short on itself. Measure the resistance, then try to find one that looks as similar as possible that you can get the datasheet for and compare. You're just looking for a ballpark to figure out if it's shorted.

 

Considering that the gap is everything between the two flanges, an extra little bit is going to make very little difference. If it’s a clean break and you have all the fragments, superglue it.
Make sure that the two lead out wires don’t short together.

 

just remove any small fragments then glue the large pieces together into same form. put pressure to keep the glue layer thin. should be as good as new.

 

Discarded computer PSUs are abundant; canibalize one for the nearest looking inductor in size and coil. Superglued will not impair it by much.

 

Hello
I have a drum coil inductor that it's ferrite is broken.
It is related to a computer PSU and part number is unknown.
Can I glue its ferrite or use with this condition.
thank you
View attachment 292545

Hello there,

I had experimented with cracked cores several years ago where i cracked them on purpose to see what would change once they were glued back together.
I used super glue but you should use high temperature glue if it is going to get hot.

There are a couple different ways this can turn out.
[1]
If the permeability is high due to no original gap or a distributed gap that doesnt alter the permeability of the core itself, then the super glue will mean you will now have a gap. A gap decreases the permeability and raises the DC saturation point. This means the inductance will drop but the ability to handle a net DC through the coil will increase such that you can have a higher DC current flowing than you could have before it cracked. So there is a disadvantage and an advantage.
Dont be fooled, in this case even a tiny gap can make a big difference. That's because the material of the gap is SO different than the core that it has almost as much effect as the core itself does simply because the gap material has a relative permeability of nearly 1 while the core material could have as much as 5000. It does depend on how high the material permeability is though.
In the tests i did i found there was a significant drop in inductance but i did have two gaps once the core was cracked because i used toroid, not open end cores.

[2]
In the second case we assume the permeability was low to begin with. In this case the tiny gap may make very little difference. Because it is an open ended core it probably has a significant drop in permeability from what the material itself is, so an extra tiny gap may not matter much.

[Conclusion]
The thing to do is glue it back together with either super glue or high temperature glue and after it dries thoroughly test the inductance. That will tell you what it IS NOW and that is most important if you want to use it for something else. If you can put it back into the original application circuit depends on how much it changed, which is hard to say without further tests or look up the core somewhere.
You can also test the DC handling ability by using it in a buck circuit and apply a load and see how much the inductance drops with increased DC load current.

 

More importantly, it depends on the function that the inductor plays in the circuit.
If it is an RF choke inline with the output of the PSU, then it should not be critical. I would simply solder the inductor back on to the board while leaving out the broken piece.

 

Thank you for reply. This is PCB image:

 

Seems to be a problem with your link to the image. You may need to upload the image again.

 

Seems to be a problem with your link to the image. You may need to upload the image again.

I uploaded it again.

 

Thank you for reply. This is PCB image:
View attachment 292556

Hard to tell what it is being used for but it's a power inductor, although lower power than the other inductors of course.
It's doubtful that it is part of an oscillator. Could be a post power supply filter which has an inductance that is not critical at all.
I guess you cant get a schematic that would tell the whole story.

 

It's a low-inductance high-current part judging by the size of the wire. I'd agree that it is a supplementary LC filter on a secondary output.

 

"Moment" glue or by chemical name cyanoacryllic glue (often sold in 1 cm3 tubes) makes extraordinary thin (!), strong and drying in seconds stich. Most of uses ferrites may be glued with that with minimal loss of quality.