Boiler Feed Water Pump Heating

It would be wise.

However, if the motor and circuit protection co-ordination is correct, and the pump is siezed, then the arrangement will trip-out on overload.

If it's not rotating you need don't have a boiler feed water pump. You have one of those ubiquitous boat anchors.

It should be checked to make sure it's working....different boilers have different check lists for startup....and different operators sometimes customize the checklist to correspond with current conditions....You should have a startup checklist that is followed and checked off with readings noted for maintenance procedures...This keeps a history of the boilers' operating characteristics for reference....

http://www.ryancompanyinc.com/customer-boiler-startup.html

Hopefully, this is a homework/ test question? For you to ask this type of remedial question shows you are not familiar with boilers and should not be working on or around them. There's too much at stake for a simple screw-up that would boil down to a catastrophic explosion.

Is this related to the thread Increasing of Impeler Diameter in any way?

No it is related to multi stage centrifugal pump only. Is there a chance of pump seizing or shaft bending or broken if the pump was hard to operate before start up and not checked free rotation before startup.

A pump can seize up at any time, usually from bearing failure...shaft bending usually only occurs in really big pumps from sitting dormant, or when exposed to extreme heat...I don't think I've even seen a pump shaft actually break, or may have and forgot, in any case probably extremely rare...I have seen them form cracks...I've never seen anybody try to hand spin a pump before startup...But you always check them after starting for proper operation....Now this is just my personal experience, your situation may be different, you might have equipment I'm unfamiliar with....I would check with the pump manufacturer for any operational recommendations that might deviate from the norm....

I tend to agree with SolarEagle in reply #8. But, considering the discussion about "Watch Your Units", I wouldn't be surprised to find mis-matched parts within an assembly. Usually the free-rotation of a motor shaft changes slowly over time and gives signs/symptoms before a sudden failure. Even tho you might not have to check it every time, it would be a good idea to check the characteristics when brand new for base-line data, then once-in-a-while thereafter to check for changes/trends to anticipate failure before it actually happens.

It is wise to check the free rotation after heating for start-up. If the pump is kept in hot stand by condition, there is a rare possibility of pump jamming. If the pump is in cold stand-by, then you should check the free rotation of pump before start-up. Some manufacturer like KSB not provides worm-up system in there some model of pumps like CHTC 4/12, which we have in our 120 MW units, but we have experienced pump jamming during start-up when the pump kept in stand-by for a long duration.

This statement, "the pump was hard to operate before start up," should have been an indication that something was not right.

It should have been checked immediately.

Just by touch you should be able to tell if it's running, If it's the type with a big screw in the middle unscrew it & you can see if it is spinning, If not put a screwdriver in the slot & give it a turn if it starts it should be ok but I would look to put a new pump in as soon as possible,

Bazzer.

Yes if it has been warmed up from cold. Yes if it has been on hot standby for a lengthy period.

The shafts of multistage boiler feedwater pumps are "slender" and as such have a tendency to sag over time or to go walkabout during heating. Often the the wear rings are made of galling materials, so the slightest rub caused by slight thermal bending can result in catastrophic failure due to galling of wear rings and neck bushes.

Is someone telling you it's NOT necessary, then , Mildred?

U'r not actually telling us what type of system it's on, is it domestic or commercial? totally different types of pumps.

Bazzer

Multistage (11)high pressure1600PSIG 200GPM flow.

Please explain why the pump manufacturer can not, or will not, give appropriate advice either in the user manual that came with it, or over the telephone?

Please explain why the facility would prefer to put its trust in the hands of a bunch of anonymous strangers on the internet, who individually and collectively cannot see anything of the installation, rather than the original equipment manufacturer, who knows it intimately and whose representative may well have been present upon original commissioning?