Submersible Turbine Pump Removal from Wetwell

[joeriess]

I've got a 42' deep, 6' dia wetwell drawing water from an infiltration gallery next to a river. Currently, we have 3 small (250 gpm) submersible vertical pumps installed, but we plan to replace them with two 450 gpm @ 85' TDH submersible vertical pumps (Grundfos or equal). The exisitng pumps are rigidly coupled to 4" discharge piping, so we have to enter the wetwell, uncouple the pumps, and hoist them out from above with a pulley system. Weight's not an issue, these are only 200 lb pumps. The problem is, we want the new pumps to be installed such that we don't have to enter the wetwell. I've considered flexible drop pipe (e.g. Boreline), but don't know about the longevity. I'd rather find a way to put a 90-degree elbow on the pump discharge and a "quick connect" type fitting to the permanent discharge piping. Like a pitless adapter, or quick connect assembly that Flygt or ABS uses for submersible non-clog pumps. Something that uses the weight of the pump and a wedge-system.

Any ideas would be appreciated. Thanks in advance.

 

[Artisi]

Trust you have personel trained and with appropriate safety equipment to enter confined below ground enclosures.

Have you checked the Flygt or ABS pump range for pumps capable of this duty with quick connect discharge couplings.

 

[joeriess]

Yes, we're trained for CFE, but prefer not to enter tight spaces if we don't have to.

Regarding Flygt/ABS/KSB style pumps (submersible centrifugal non-clog), I initially considered these, but the efficiency is very low (60% at BEP) compared to submersible turbine pumps (80%). At $.41/kwh, this makes a big difference in annual electricity costs.

 

[hydrae]

Talk to Maass Midwest, they make the larger pit-less adapters, and can probably build what you are looking for.

I can imagine one of the standard units, add a 150lb flange for the riser pipe, then additional 'drop' pipe above the pit-less. Then you could remove and replace the pump just like a well pump

http://www.maassmidwest.com/maasshome.html

Hydrae