Pump Alignment

You need to align the Pump with the Motor Shaft. Check the balance of the rotating coupling. If misaligned you hear Ke Ke Ke Ke KE KE KE KE KE..... and it gets louder n louder . Then KAAAAAAAK. That means the Shaft jammed with the Rotar and that means YOU LOST THE MOTOR.

Thanks, Ducon!!!

I had expected some kind of guidelines or procedure!!!

Cheers,

Ash Bandy

Honestly I learnt it this way and it was an EXPENSIVE first-experience. My best advice take your male/female coupling on a lathe and run it to see if they wobble or not. Ask the lathe guy to balance it. Then align & level the the pump & motor with the coupling. Then you are CAREFREE.

I really love this type of answers. Alignment of rotating equipments are a basic thing that we learn-

Ducon: did you record the noises or made-up ? any way AVI files can not be loaded here. You missed out the noise when the overstreesed flange bolts fail - may be

inlet - whooooooo (air suction)

Outlet - Hoooooosh (oil spray)

Off topic: How can anybody help when we dont know the pump size, capacity, fluid, temperature. foundation, and so on.

All the instructions i am sure are on pump manual.

Just try to align Boiler feed pumps in the same way as a 1/4 HP coolant pump and you will understand what I mean.

But Ducon principle is applicable for both why don't you expand it to be a "Ducon's law of alignment diagnostic"?

- Align pump and Motor to specified value, depending on your procedure and tools available with coupled condition. uncoupled condition

- Tighten foundation fasteners and recheck alignment.

- Ensure the pipelines (based on their supports, rigidity etc) are aligned to flange and sufficiently nearby (depends on the pipeline design how nearby it should be, we just prefer that it should not create a stress on flange joint when we tighten flange bolts

"Ducon's law of alignment diagnostic"? Good one. Thanks sb.

Thanks for a step by step pre- alignment check method.

Only thing I forgot to mention to check the soft foot on the motor and a deflection between 0.05mm ~ 0.08mm would be happily acceptable.

Master levelling on the discharge flange.

Torquing of hold down bolts.

face and rim alignment.

The only caution I would consider other than the input you have received is in the area of how you read the alignment. If you are using standard dial indicators or feeler gauges the face readings are more significant on small diameter couplings. If you are reading on a very small diameter you may want to fabricate a rig to extend the diameter. I think the reason is obvious.

I agree Otha. Of course it all depends what kind of alignment the client has specified like conventional type, reverse (Graph plotted) or laser. Also, the arrangement I have made is like ould be used for couple of sizes and then the next rig further sizes.

Dear Friends,

It is better to tell you the procedures how you can align the specific machine. You can contact the machine vendor and ask HOW!!! For example, how to mount the pump on the foundation, how to align the pump and motor, etc,.

I feel that your question the work flow of pump installation.

When the pump arrives in the site, provided that anchor bolt is already there (embeded type, other type such as box type does not need much of work)

1. Remove all dirts and dust on the foundation and clean it as much as possible. Mount the pump on the foundation. Check the suction & discharge nozzle location along with the black ink line on the foundation. Check the horizontal levelling of the pump baseplate. Everything is completed? Then, pour the groutings. Wait for 2-3 days for curing of the grouting.

2. Pre-alignment check : This is to check the horizontal parallality between centerline of pump baseplate and centerline of pump-coupling-motor. (1st Alignment) Offset shall be corrected with the shim plates as needed.

3. Pump alignment check : Pump suction and discharge pipings are connected. Now you are really doing real pump alignment!! Offset shall be done by moving, shim plating and other way.

4. Final alignment check : This is to confirm the piping does not give too much piping load to the pump. Disassemble the pump suction & discharge piping from the pump. Check the pump alignment that you have done at 3 stage (Pump alignment check) If the result is acceptable? then it is done. If the Alignment is ruined, Repeat 3 again until you get the satisfactory result at this stage.

So, in conclusion, you need 3 times alignment of the pump during the construction stage.

If you have to allign on a regular basis, a quality laser allignment system will pay for itself many times over.

for us it was cheaper to buy some flex couplings (comes balanced at operating rpm)

we tried playing around with shims for alignment/to reduce vibration but the flex coupling seemed to worked well for us

The problem with relying on flexable couplings to compensate for poor shaft alignment is that deflecting the coupling adds load to the bearings. Given that the life of a rolling element bearing is inversely proportional to the load cubed, that will drastically reduce the bearing life.

From a life cycle cost point of view, you are much better off aligning the shafts correctly.

Also, for a pump or turbine, you don't want any piping strain. If you have strain, you have the possibility of distorting the casing and reducing bearing life or worse. I once saw a 2000HP pump bound up by piping strain.

2000HP pump bound up by piping strain. Good Lord! I bet the guy responsible left town and still untraceable.

It was a shipboard condensate pump. The mechanics who installed it found a 3/4 inch mismatch between the pump discharge flange and the piping. Instead of re-targeting the piping, they used a chain fall to pull it into alignment.

Why can't we go with a designed flexis at suction and discharge??

In most cases you can.