High capacity raw water pumps - Submersible or vertical shaft driven pumps
High capacity raw water pumps - Submersible or vertical shaft driven pumps
(OP)
Hi all,
Decision between submersible and vertical turbine pumps for raw water pumps has been discussed under thread 407-233951.
But my problem is more towards high capacity end in the region of 1250 L/S at 40M. (750kW)
Decision is almost made in favor of vertical shaft driven pumps, mainly considering maintenance and handling issues.
But there are submersible pumps capable of this duty by leading pump manufacturers.(KSB)
Can any of the forum member with experience with submersible pumps of this capacity please comment on this?
Thanks
Decision between submersible and vertical turbine pumps for raw water pumps has been discussed under thread 407-233951.
But my problem is more towards high capacity end in the region of 1250 L/S at 40M. (750kW)
Decision is almost made in favor of vertical shaft driven pumps, mainly considering maintenance and handling issues.
But there are submersible pumps capable of this duty by leading pump manufacturers.(KSB)
Can any of the forum member with experience with submersible pumps of this capacity please comment on this?
Thanks





RE: High capacity raw water pumps - Submersible or vertical shaft driven pumps
Johnny Pellin
RE: High capacity raw water pumps - Submersible or vertical shaft driven pumps
What JJPellin is describing as his problem is probably the area you need to consider most in your design. You are most likely drawing from a river or lake/reservoir which will contain sand fines whether you like it or not; even with the best of filtering. That bearing below the impeller is many times called the "sand bearing" for a reason. Many schemes have been tried to perfect the isolation and lubrication of this bearing. The best designs usually involve forced lube with fresh water or grease.
Go look at info from some of the most experienced and respected manufacturers of axial or mixed flow pumps: Johnston (now owned by Sulzer), Cascade, Patterson, Floway (now WierFloway), Flowserve (who actually use Cascade bowls and propellers).
RE: High capacity raw water pumps - Submersible or vertical shaft driven pumps
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.)
RE: High capacity raw water pumps - Submersible or vertical shaft driven pumps
Thank you for all who have given comments.
It is good advise from JJPellin not to go for "smallest, fastest, largest or longest of any particular technology"
It is applicable in this case.
River sand is a problem for vertical turbine pumps, but main option we consider is vertical shaft driven pump, although at additional construction cost. (in line with the type of already installed pumps)
So once again thank you for your comments, which made us more confident on our decision.