You ask a simple question ... but there is not a simple answer for all models of these pumps !!

Did you find the pump in a field somewhere ? .... Tell us more

Who manufactured the pump ? ... Is there any Identification of the pump size, type, model number ... or has the previous owner of the plant removed all of this information ?

What did the O&M Manual tell you about this ? ... You can probably find it on the internet..

Can you take pictures of the pump with your phone

What did a GOOGLE search of the internet tell you about this specific topic ??

What is the media and service for this multistage pump ? ... Boiler Feedwater ? ... Process Chemical ?

MJCronin
Sr. Process Engineer

First of all thankyou very much, for immediate reply.
Flow Serve/Ingersoll Dresser MakeMultistage pump,4WDXR7 Model,with7 stages.
RO Feed Pump application (desalination).O&M Manual not mentioned clearly about- Which bearing is to be locked first.Hope this will suffice to proceed further.

• https://files.engineering.com/getfile.aspx?folder=71c90b94-ec3b-49f8-b541-2

From what I can tell, the assembly is the reverse order of disassembly;
"6.10.3 Anti friction bearings
Antifriction bearings should be preassembled so that
the complete bearing set can be mounted on the
pump casing. To do this, reverse the dismantling in
sections 6.8.2 and 6.8.3."

In 6.8.2, the Thrust bearing is the first to be removed, so it should be the last to be installed.

I'm not sure if this helps, but I would say that the radial bearing should be locked first.