Manipulating this kind of electromagnet?

[Hol]

This is an electromagnet that has both poles on it's surface. Example .
When it's surface is in direct contact to a ferromagnet it generates forces up to 480 lb.
Now it's manufacture states that it's not possible to create a repulsive force... I would disagree and would ask you if this is true?

Assuming the surface has both N & S poles, bringing an equal electromagnet like it, and orienting it in such a way N meets N and S meets S, there should be a strong repulsive force( Assuming Power input on both is the same).
Or am I missing something here?

The manufactures statement: [highlight #EF2929]Can electromagnets be used to repel as well as attract?[/highlight]
As they are sold, minimal to no repel can be achieved as they are designed to attract. What is needed to repel is a coil around an iron core with no outer shell. This configuration places a north pole at one end of the iron core and a south pole at the opposite end. The electromagnets as they are sold have a south pole and north pole on the same end. One pole is on the outside ring or shell and the other pole is located on the center post or core.

Can they be repelled?
And is the repulsive force near the attractive force?

 

[IRstuff]

From the diagram you cited, the field at far end of the coil, which is where the actual pole of the electromagnet resides, is steered to the near end by the soft steel shell, as the manufacturer explains. This makes the center of the coil face one pole, and the shell ring on the outside the opposite pole, to maximize the pull force of the electromagnet. This is similar to the magnetic circuit configurations of transformers and motors.

As the manufacturer explains, you would need to remove the shell to have only one pole on the coil face.

TTFN
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[Hol]

@IRstuff
Is there a specific name to this configuration? That I can research more about?

I'm imagining two poles on one side, I understand that point. However, why can't the repulsive force be achieved here using an identical product?
Here is why I'm confused...there is a magnetic field, and it's known that if we introduce a pole to a similar pole a repulsive force will emerge.
If this is experimented what might be the results?

 

[IRstuff]

I suggest you do some basic research. Since you have both poles on one side, you cannot make it repulse anything

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[Compositepro]

Hop, I think your misunderstanding is in the difference between a ferromagnetic material and a magnet. A ferromagnetic material, like iron, will be attracted by a magnet and not repelled. Magnetized iron is a magnet and can be replled as you describe.

 

[MagBen]

This specific two-poles desgn is for attrative force, when attracting the Fe or steel piece, it forms a close magnetic curcuit with limited flux leakage, and so maximized force. Even without the steel piece, the flux is self-contained from N to S, without much flux flowing in open air.

When you place two identical electromagnets close together N to N, S to S, you would probably still get an attractive action, but will be off-center (mis-match) since N will find S, and S to N. If you can force two magnets against perfectly in a line, you could get a repulsive force. I would guess the repelling force is smaller than attraction.

 

[Hol]

Usually I'd find electromagnet's with the capacity of attracting(i.e holding) Fe in massive rates of force.
Is it it possible to build an electromagnet that could repel( similar electromagnets) with large forces using the same materials however in a different designs?

 

[IRstuff]

As explained in the passage you quoted, if you eliminate the shell from the magnet you have now, you would have the electrical equivalent of a normal bar magnet.

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[Hol]

What is common is an attractive electromagnet that is able to produce forces above 5,000 lb easily. However, it more difficult to generate similar magnitude of force with a repulsive force. Is it practical to build a similar spec, similar input or close to it, and generate massive repulsive forces?

@IRstuff if the shell is removed do you think the performance would drop greatly when it is able to repel opposing poles?

 

[IRstuff]

The physics are not symmetric. The flux density of two repulsing poles is less than that of two attracting poles.

http://armymedical.tpub.com/md0950/md09500047.htm

shows that there are more field lines participating in attraction than in repulsion

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