Dry well submersible pumps 1

[Lan123]

If required can a dry well submersible pumps also manufactured in guide-rail mounted configuration?

Also what does a impeller of a vortex type submersible pump look like?. Is it similar to an impeller of an axial, radial or mixed flow pump?

Thanks

 

[Artisi]

Have you ever considered an internet search for this information, or bothered to check on the websites of the major pump manufacturers and suppliers of this pump type.

Might be a good place to start instead of asking other people to do it for you.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[bimr]

When installed in a dry well, the submersible pump is bolted directly to the suction and discharge piping. It is supported on feet and mounted on a concrete foundation or directly onto a pipe bend.

So there is no reason to manufacture a submersible pumps in guide-rail mounted configuration for a dry well application.

A non clog vortex impeller is used to pump sewage.

http://www.pumped101.com/impellers.pdf

 

[Lan123]

bimr

Thanks for your reply. There are two pumps installed in a below grade dry well in a waste treatment plant. The access to the dry well has some physical constrains. The operators would like if the pump and the motor can be serviced from above grade. They don't want a separately coupled motor mounted at above grade as this obstruct free movement at the floor level.

 

[bimr]

Don't think that what the operators want is possible.

One alternative is converting the wet well into a submersible lift station.

Another alternative is installing the pumps above grade. Gorman Rupp has above ground lift stations.

The alternatives depend somewhat on the size of the lift station and the piping arrangement.

 

[DubMac]

It is true that the pump's discharge should be hard bolted to the discharge piping down in the wet well; but it can be worked around.

You must have provision to unbolt the discharge pipe up at the top of the well, and then pull the pump and discharge pipe out together. Most of the submersible vendors will advise on the specifics of the rail system, or it can be designed "in-house" if you have the engineering capability. I know Paco, Hydromatic, Meyers, Flygt,etc. used to offer rail systems for their dry pits.

There is a need to be sure that the motor is suitable to run in a dry environment, since most submersible motors rely on being submeged in liquid for cooling. Either will need an oil-filled motor, or one that is sized properly to live on air-cooling.

 

[bimr]

DubMac,

Note that the suction pipe as well as the discharge pipe have to be connected and bolted. Refer to the picture. Don't believe there is a method to use drop in connections to seal two separate connections at the same time.

http://www.fmpump.com/resources/images/20660.pdf

 

[pumpkind]

One way to get a better answer will be to identify the manufacturer of the 2 existing pumps and put a question to them

 

[TenPenny]

I don't believe there is any physical reason why the dry-run submersible could not be fitted to the guide rail/lift out system. I doubt that it is common, but if you refer to the fm pump brochure on the link above, you can see that there is no real reason why the water jacketed dry run submersible motor could not be fitted onto the pump casing with the lift out discharge.

 

[Lan123]

Folks thanks for all the valuable comments. Now I know what needs to be done.

 

[bimr]

There is a physical reason that dry fit pumps do not have a drop-in discharge connection. A drop-in connection used in a wet well is not required to be a water tight connection. If the drop in connection is installed in a dry well, leaks from the drop-in connection will occur which will flood the dry pit.

The purpose of the guide rail is to allow the pump to be centered on the drop-in connection when the pump is lowered into a wetwell during installation. Therefore personnel can service the pump without having to enter a wetwell.

In addition, a dry pit pump must also be unbolted from the suction side as well as the discharge side so personnel would be required to enter the dry well in any case.

The drop-in connection is not practical in a dry pit amd there is no reason to use a guide rail. It would make more sense to reconfigure the lift station.

Compare wet well arrangement P to dry pit arrangement T.

 

[TenPenny]

I have to admit - I was, well, you know, the word that a man tries not to say, especially to his spouse, w...w...w...oh, you get it, I still can't say it.

There's no reason that a run-dry submersible pump can't be put on a guide rail, but if you want a dry pit, that would imply a physical connection between the inlet of the pump and the piping, which would be very hard to do in a lift out arrangement. Without that suction connection, the pit wouldn't be dry. It certainly could be done, by building a custom arrangement to put the suction and discharge connections onto one bracket some how, but it would be reasonably impractical.

 

[DubMac]

I too must admit i was......, well you know...... I don't know what I was thinking with pulling a dry pit up rails.

Bimr was right; can't be done because of suction connection. You could do it with hoses connected, but like Tenpenny said, would not be practical.

 

[vpl]

Bimr -- I think what TenPenny and DubMac are trying to say is that you were correct and deserve a star. I've given you one on their behalf.

Now wasn't that simple? You don't even have to use the "wrong" word.


Patricia Lougheed

******

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[stanier]

http://www.chopperpumps.com/apps_muni.html

Vaughan have a range of digester pumps that may fit your bill if you are looking for a Vortex pump. These can be mounted inside or outside of the digester.



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