Submersible pump

[Maker]

Found it in a skip last night;

It was shiny, I couldn't resist.

It has quite a strange arrangement inside;

Firstly the stator is completely welded shut, even inside its just a stainless tube, how do the flux lines get out?

Then the armature is laminated as you'd expect but it has no windings.

There were seals on each end of the motor but the space around the rotor was full of water nonetheless, perhaps that's why it was skipped.


The writing on the body says "1~" which I would intepret as single phase, and the 3 pin power connection (See the second pic) only fits one way round, which also points to it being single phase, but the wire is 4 core;

But as far as I know, brown, black, blue and yellow/green aren't standard three phase colours, more like single phase but with some random black wire in there too

Anyone know know how the motor works? Or what this confusing wiring is? Or how to get the pump side of it apart?

There's no fasteners anywhere I can see, and I can hear water inside it but nothing has leaked out.

Oh, and I've got a bigger Grundfos one somewhere.

 

[daleyd]

Is the extra wire for a switched live - from a float switch perhaps

 

[carbon]

It's an induction motor so only has windings on the stator. The ones I have worked in have been multi plate impeller pumps and usually have to remove one impeller at a time

 

[knighty]

water flows around the armature to keep it cool

looks like a borehole pump to me

extra wire is probably for some kind of insulation test. so you can have a little guage back where it's plugged in letting you know if the insulation is starting to break down before it breaks down enough to blow a fuse


iirc.... bloody expensive pumps when they're new :-o

 

[Gareth J]

iirc.... bloody expensive pumps when they're new :-o

This^^

Before you delve too deep, search around and see if you can find someone who repairs these. It may well have value as an exchange unit. Worth selling on as is or even getting it repaired/exchanged and selling the refurbished one.

 

[daleyd]

Oh just looked again - the separate wire maybe a support wire for when you pull it up - to avoid straining the electrical wires ? Don't know, just a guess- I've only seen them on pendant wires before for overhead cranes.

 

[Maker]

Got the pump apart, the two ends are screwed into the "body", just a stainless tube with a fine internal thread. The ends were a bit bent in so it wasn't easy to unscrew, and then the 14 impeller pieces needed knocking out one at a time.


This looks like the motor, I think I've got the "PSC" model, see page 5. Looks as though I need a capacitor and possibly a controller to test it.

water flows around the armature to keep it cool

The PDF above supports this too, but it seems weird that there's rubber seals and the like if water is supposed to get in.

This^^

Before you delve too deep, search around and see if you can find someone who repairs these. It may well have value as an exchange unit. Worth selling on as is or even getting it repaired/exchanged and selling the refurbished one.

Any idea where I might find such a place?

Oh just looked again - the separate wire maybe a support wire for when you pull it up - to avoid straining the electrical wires ? Don't know, just a guess- I've only seen them on pendant wires before for overhead cranes.

I wouldn't have thought so, it's about 15kg, that seems like a bit much to hang off copper wire, plus there's a lifting eye on one end.

 

[daleyd]

I didn't realise it was copper - I thought it was steel wire, bit hard to see on my phone !

 

[MrFluffy]

If its anything like the submersible pumps I've worked on, the primary failure mode is the shaft spalls where it passes the seal, then the damaged seal surface destroys the seal and the motor section fills with water and shorts out the supply.
I machined one and fitted a sleeve to it and ground it to size and fitted a new seal to fix it for someone as a experiment and that was ok, if labourious, but the next one that I had problems with I just stuck in the bin.
Some of the less quality ones don't even have stainless shafts inside where they corrode and they are even worse for this.

Depends on its value if its worth fixing or not I would say.

 

[Gareth J]

Any idea where I might find such a place?

Nope, sorry. I'd just do some googling or phone a couple local bore hole companies and see if they offer/use an exchange service. As you've got it this far apart though, maybe you can fault find yourself.

Mine you, I've no idea about the value of your particular one, it may or may not be worth it.

The thing should have been dangled by a rope alongside the power cable.

 

[normspanners]

looks like a borehole pump to me

yep the extra wires could be for a remote capacitor more like.

 

[Maker]

There's all the pieces after a dip in the ultrasound tank. Nothing appeared to be worn/rusty/damaged but there is one pretty big problem...

I can't reassemble it.

Remember I said the internal thread on the pump casing was a bit chowdered making it hard to unscrew - Try screwing it back on.


And the motor won't go back together because there's an O-ring in the way;

That O-ring should fit snugly into the bore of the stator but instead it catches on the end making it impossible to press it on properly.


I didn't actually notice what the problem was at first and have scored the O-ring trying to press it down.

Anyone know how to fix either of the above problems?

 

[awemawson]

Can you use a large Jubilee clip like a piston ring compresser to squash the O ring?

 

[Robotstar5]

Silicon grease?.

 

[normspanners]

if it has been a leachate pump it could have effected the rubber and expanded it, horrible stuff leachate.
you can get thread files with internal thread chasers on the end to help with internals

 

[Seadog]

If the tube section isn't too heavy and the flat not too large, you could perhaps dress it out using a large piece of aluminium bar held in a vice as a mandrel. and then tapping round the damaged area with a suitable hammer to reshape.

 

[Rig Pig]

P

Got the pump apart, the two ends are screwed into the "body", just a stainless tube with a fine internal thread. The ends were a bit bent in so it wasn't easy to unscrew, and then the 14 impeller pieces needed knocking out one at a time.
View attachment 110539

This looks like the motor, I think I've got the "PSC" model, see page 5. Looks as though I need a capacitor and possibly a controller to test it.


The PDF above supports this too, but it seems weird that there's rubber seals and the like if water is supposed to get in.


Any idea where I might find such a place?


I wouldn't have thought so, it's about 15kg, that seems like a bit much to hang off copper wire, plus there's a lifting eye on one end.

Panks pumps in Norwich perhaps???