My Turbo and Homemade Driver

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Nnnnnnn
Posts: 58
Joined: Tue Jun 13, 2017 6:25 pm
Real name: Niels Geerits

Re: My Turbo and Homemade Driver

Post by Nnnnnnn »

So I removed the conic nut and the top came right off. I can see the bottom bearing but it won't budge. I have tried pushing it out from the top with an allen key but as I said it will not move at all. So I think that it must be retained by something else, however I have no idea what is holding it in place. All the drawings do not mention anything. In addition the TPU 170 manual (different pump) has a guide with pictures. In that guide it also seems like the bearing should come straight out.

Edit with some extra info. I have a hunch what maybe holding the bearing in place:
tmh.png
In this drawing you can see that there is some kind of retainer below the bearing. I checked the holes that I circled red and found that they are threaded. So I think I could pull the retainer out if I put some screws in there and pull on them. But it is hard to tell because the holes are very small. However I would also think that pushing from above would force the bearing and the retainer out (but that hasn't worked and I do not feel comfortable applying more force).

Second edit: After further examination it could be that the retainer is being held in place with very small hex screws. But despite good eye sight it is impossible to be sure.
Peter Schmelcher
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Joined: Sat Nov 13, 2010 1:56 am
Real name: Peter Schmelcher

Re: My Turbo and Homemade Driver

Post by Peter Schmelcher »

Niels attached are some pics of a tph 055 that might provide some useful insights for your repair. Mine was missing the other bottom parts when I got it. BTW the tph magnetic bearing also has a 6x13mm ball bearing for takeoff and landing.

I investigated high speed ball bearings some time ago. The only inexpensive types I know of are for dental equipment which has fantastic rpm but unfortunately limited sizes.

-Peter
Pump bottom shaft
Pump bottom shaft
Bottom shaft in pump body
Bottom shaft in pump body
Attachments
Magnetic bearing with C-clip removed
Magnetic bearing with C-clip removed
Ball bearing inside magnetic bearing with preload washer and C-clip removed
Ball bearing inside magnetic bearing with preload washer and C-clip removed
Jerry Biehler
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Location: Beaverton, OR

Re: My Turbo and Homemade Driver

Post by Jerry Biehler »

You need a pin spanner to unscrew the piece that is holding the bearing in place. I have gotten away with finding two drill bits or dowel pins that fit snugly in the holes and grip the both as close to the surface as I can and unscrewing it. It shouldn't be that tight, it does not need to be. If that does not work measure the distance between the holes with a digital caliper and take a small bar of aluminum that will fit in the recess where the plastic cap was and drill two holes to match for pins. Probably something like 1/2" thick, 3/4" wide and about 2" long.

You could also try something like this: https://www.amazon.com/Andoer-Professio ... ench&psc=1
Nnnnnnn
Posts: 58
Joined: Tue Jun 13, 2017 6:25 pm
Real name: Niels Geerits

Re: My Turbo and Homemade Driver

Post by Nnnnnnn »

After hours of cursing I finally did it. The retainer came out using an aluminum bar with 2 holes drilled into it, 2 allen keys fit into those holes, which also went into the holes in the retainer and a wrench to hold the aluminum bar and apply the torque. The retainer was so tight that the torque bent the aluminum bar and broke a piece off of my low quality allen key.

The bearing, o rings and anti vibration ring had a phenomenal amount of black and yellow crud on it. I gave the bearing a spin in my hand and was able to feel the friction (there is probably crud inside of it which would destroy the bearing at high speed). It did not look like any of the balls were missing though.

In addition the interior of the pump had a criminal amount of backing pump oil residue inside of it, which I cleaned out. I still have to clean the upper stage. According to the manual you can just dunk it in some alcohol.

On monday I will ask Alpine to send me a replacement. Pfeiffer recommends to replace the anti vibration ring, but mine seems fine so I will probably just re-use it. I will also have to order some oil.

Peter thank you for the images. That ball bearing close to the magnetic bearing is an emergency bearing as far as I know. It can save the pump should the magnetic bearing fail. Those takeoff and landing bearings also exist in those fancy hipace pumps that use active electromagnetic bearings. I have been told that sometimes this emergency bearing needs to be replaced. But first I will just replace the lower bearing and see if that gets rid of the strange sounds.
Jerry Biehler
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Location: Beaverton, OR

Re: My Turbo and Homemade Driver

Post by Jerry Biehler »

You dont order oil, you replace the cartridge. The landing bearing on top is just for if the machine the pump is attached to gets hit or something while the pump is running, these pumps are not like maglev pumps which set the rotor down on a bearing when it is shut down. On my big maglev (2000l/s) I you get 5 landings at high speed before you have to replace the bearing. I have the turbo on a UPS to make sure I never lose power while it is running.
Nnnnnnn
Posts: 58
Joined: Tue Jun 13, 2017 6:25 pm
Real name: Niels Geerits

Re: My Turbo and Homemade Driver

Post by Nnnnnnn »

Oil cartridge and lower bearing have been replaced with pfeiffer parts. Most of the sounds are gone, however I think I may have messed something in the upper stage up. Before I replaced the bearing I opened the upper part of the turbo to look at the rotor. I did not take anything apart I looked at the magnetic bearing and then put the upper part with the flange back on. Locked the screws which push the magnetic bearing down and thus mounts the blades on the bearing. Then today I put in the new lower bearing and put the pump back together. Once it was reassembled I gave the upper blade a push and noticed that the friction had severly increased! The blades spin and then come to a rather abrupt halt. Here a video:

https://youtu.be/zn0KrE6dhJk

If I put my ear on the flange I can kind of hear the friction. It is obvious that the source is somewhere in the upper stage, but I am not sure what exactly the cause is. Anyone have any idea what I did wrong?
Jerry Biehler
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Location: Beaverton, OR

Re: My Turbo and Homemade Driver

Post by Jerry Biehler »

I think it is fine. You are going to need to run it up to speed and see how it does.
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