Pump Base Plate Leveling caused deflection

[bmw318be]

Hi expert

I had a pump set that are perfectly aligned at workshop (Ground flooring Surface) before installing to the Site foundation. The foundation has anchor 3 anchor bolt side by side and 6 LEVELLING SOLE PLATE which is side by side as in the below photo link.

After levelling the Skid to the foundation, the base plate tend to deflect by 3-4 mm, this is done after the Skid is fully bolted to the anchor bolt and leveling indicator at every side (6 basically)

Noted the actual shape of bottom sole plate (2 inch by 2 inch with thickness over 1.5 inch, shape is the rectangular and welded rod as shown in illustration

1. Would the uneven surface where the Sole plate are rested caused this deflection ?

2. Does the Sole plate height inconsistency at point 2 and 5 would affect the co planar of the surface ? observation section 3 and 3 deflected up by 4 mm



4. Should we flatten the foundation so the sole plate could rest in parallel to the foundation ?

5. Any guidelines of levelling at site ?

Picture shown

https://www.dropbox.com/s/13p78rbq25u1if3/Deflection after levelling.png

 

[desertfox]

Hi

Once the base is level why not try placing packers under the frame very close to the bolt and that should stop the base deflecting excessively while tightening the bolt down.

 

[StrucPatholgst]

That's an unusual way of doing it. Seems like a waste. Jam nuts and washers on the anchors would have been sufficient. Set the anchor bolts, get the frame level with the jam nuts, and crank down on the anchor bolt nuts to lock it in place. Half the hardware, half the holes, no welding.

 

[msquared48]

Back off on bolt #5. It's driving it up the corner of the skid.

Mike McCann
MMC Engineering

 

[bmw318be]

Hi, I give a clear illustration here on the case.

https://www.dropbox.com/s/ii7bqhurbcbn8hs/Grouting.pdf

1. Should we make sure the soleplate used is coplaner at 6 points by checking it before mounting the skid to the chipped concrete. My skid has a flat small plate machined surface at the bottom where the location of anchor bolt hole and leveling bolt. I managed to pre align this to 0.05 - 0.1 mm coupling alignment.

2.The Circular soleplate (2 in x 2 ) has different height as illustrated in the attachment link
3.The soleplate which was used to prevent the leveling bolt from digging into concrete, however in this case it was pierced through by the leveling bolt (significant depth is observed during the taking down the skid )
4.It seemed that too much tightening force on the tightening down the Anchor nut (Not sure if this is done during leveling down)

5. Does anyone knows if The same thickness sole plate should be used here so the 6 point of soleplate has a co-planer between + - 0.05 mm
The Skid has a flat soleplate where the anchor bolt hole and leveling bolt side by side this would come into contact with ground

6. Where should the leveling gauge is placed, is it on the mounting Surface or on the C channel ? point 1- 6

7. What Is the correct procedure, the anchor bolt nut should be tied down after all the 6 points are level ?

 

[desertfox]

Hi

Well really you should be following the pump manufacturers installation manual, I used to work at SPP pumps on contract and if you follow the link below it will show you how to install a pump set similar to the one you have.

http://www.spppumps.com/linkservid/6452438F-3A43-411D-A44A761077367F16/showMeta/0/

Looking at your photo's and as I pointed out yesterday you need to support the pump frame lower flange so that when you tighten the anchor bolt down the frame doesn't distort significantly.

desertfox

 

[bmw318be]

Hi desertfox,

Thanks, would like to understand how
You overcome deflection on one end motor side other than add shim
To soleplate, because i dont think, they allow to put shim underneath the soleplate as what is in your instruction manual.


By looking at some of the client soleplate, it should not digging into by the leveling bolt,means it has large amount of torqing force bolt down by the anchor bolt to bring the mounting plate lower.

If i am able to achieve co planer on the flat ground, is it right to say I dont need much adjustment on the leveling screw and anchor bolt.

For your pump, do you place the leveling gauge on the equipment mounting surface ? Would you elaborate techniques used

 

[bmw318be]

Dessertfox,
The 1st of my illustration was not clear,the skid is actually distorted down by looking at my 2nd illustration, the pump to gearbox shaft alignment was close to pre aligned, however motor rend to be higher now.


Does it means the anchor bolt at 1 to 4 was bolted down too much due to lower elevation or tilting skid. Where the number 5-6 anchor bolt was high.

Based on your instruction, the anchor bolt has also a plate or shims pack, does this should be come into contach with the c channel bottom
Surface, and if it is not, you need to add shims so when bolt it down it wunt deflect much.

I like to know how you level the motor side if it consider the high sides

 

[desertfox]

Hi

Recently I oversaw the installation of about 25 pumps similar to yours, these were not SPP pumps but the manual stated that the fabricated base should be at least 25mm above the concrete plinth to allow for the grout.
We aligned the frame or soleplate as you call it at the corners where the bolts were situated by using packers and taking level readings using an engineers level and got it within 0.1-0.2mm.
We also took level readings as the frames were tightened down to try and ensure it wasn't distorted to much.
Finally we aligned the motor/pump coupling with a DTI to within 0.1mm and any adjustments made to get that alignment were done by shimming the electric motor.

Hope that helps

 

[desertfox]

Hi again

I would add some more points, you say the pump set was perfectly aligned at the workshop but at that stage the skid wasn't supported on six adjusting screws and once it is supported in that manner the whole frame is subject to bending due to self weight of frame plus pump and motor.
Secondly with the frame supported on six jacking points, you now proceed to tighten the anchor bolts, however there is nothing to stop the bottom of the frame distorting because there is nothing directly under the frame at the anchor bolt hole, so as you tighten the anchor bolt, the bolt gets tensioned until it overcomes the frame stiffness and then the frame distorts, so until that issue is addressed your going to have that problem.
Finally I don't know what anchor bolt torque you've been instructed to use but the torque setting should be calculated based on any vibration the unit might and also to prevent to frame uplifting in the event of the motor seeing an overload so backing off the bolts to level the unit is not a good idea in my humble opinion

 

[dhengr]

I agree with Dessertfox, follow the pump manufacturer’s installation instructions, they know how they want it done for their skid arrangement and design. And, if you have problems, they are the ones you should be going to with your questions. Again, they have probably heard that same question before, and they should know the answers. It appears that the cross beams for the components are set so that the components are aligned when the skid side rails are level. However, I do think that is a kinda crazy leveling and hold-down arrangement, since you can’t tighten down the anchor bolts, once the leveling bolts have been set, without distorting the skid rails. It appears to me that the anchor bolts are set in sleeves, in the concrete, for a little lateral flexibility during setting, and the sleeves project too high. I would cut the sleeves off at the top of the concrete, but don’t notch the A.B’s. Then, I would put a nut and washer on each A.B. I would use the leveling bolts to level the skid, measuring to the top of the skid side rails. Then, run the afore mentioned nut and washer up to touch the underside of the side rail, finger tight plus 1/4 turn +/-. Now, tighten down the top A.B. washer and nut. This will prevent the skid from deflecting from the A.B. tightening. Then check all levels and alignments as Dessertfox suggested. I suspect the leveling bolts will vibrate loose over time unless you put a locking nut on the underside of the side rails on them. Or they may crush the rough conc. under their foot pads over time.

 

[desertfox]

Oh I posted before I saw your next post sorry about that.
The anchor bolts should have a torque or preload specified so that the frame doesn't get tightened more in one place than another and yes the spacers should be a nice fit under the frame at the anchor points after its been levelled.
Who's pumps are they and do you have an installation manual for them?
Also who won't let you put spacers at the anchor bolt points?

 

[bmw318be]

Hi Desertfox,

The skid when installed at plinth was
Dismantled and this was the procedures.

The installer was trying to level the skid and I am not sure if there is sleeve underneath of anchorbolt, if thre is then skid would rest there and levelling screw could be lifted up.

I ve observed all weight rested on 6 levelling bolts and the soleplate was placed to support the skid and prevent digging in, however i observed they did not use the same thickness of soleplate.


It is possible when the centre 3 and 4 are tighten down with anchor nut to level and as you mentioned no sleeve at anchorbolt to hold frame then it deflect the centre causing it 5 and 6 mounting higher

 

[desertfox]

Hi

Yes its possible that when points 3 and 4 are tightened down the frame could deflect and points 5 and 6 would appear higher than 3 and 4.
I don't think the soleplate thickness matters that much because you can alter the level of the frame by the adjusting screw.
They way to install these units is:-

1/ level the frame on the jacking screws.

2/ When the frame is level, support the frame on packers adjacent to the anchor bolts to prevent frame distortion when
tightening down.

4/ Tighten bolts down and monitor the level while doing so.

5/ Adjust the final levelling when the couplings are fitted by fitting shims under the motor feet etc.

Now you still haven't told us who the pump manufacturer is or whether you have an installation manual or not.
This manual is important for not only mounting the frame on its plinth but also for the alignment of pump,motor and gearbox,some manufacturer's quote shaft offsets between pump and motor/gearbox during cold alignment to allow for expansion and the rising of the rotating shafts during start up and running.

 

[bmw318be]

Pump manufacturer is yildiz, they do not have a base plate installation manual, the base plate was fabricated by vendor here. We got to use our own descretation and our scope here is to supply whole pump with a baseplate.

So 1st procedures is to mount the skid to the 6 anchorbolt. I believe the installer in my case is using my leveling bolt to increase the elevation for as you mentioned 25 mm above chipped concrete for grouting purpose. However after leveling,All 6 they probably tighten the anchor bolt 3 and 4 till the frame come into contact with sleeve, i am not sure either if the anchor bolt has sleeve which act as support to the frame.

I would check this, so usually the tie down of anchor bolt is only done after 6 points are level right and where you place the levelling gauge, is it by the side of c channel levelling bolt ? .if you could share me the photo of your installation steps would be great


Anyway, after skid is dismantled for milling deeper at one sides, we observe it returns to normal. However we still give them provision for deflection which I think the installer should have procedures of not deflecting the skid here.

 

[desertfox]

Hi

My first question is then, how level was the skid after it was made?
I presume the skid as got machined pads for the pump/motor/gearbox mounting feet, now if you can get an engineers level onto any of the area's that have been machined on the skid with the pump/motor already mounted then that's the area I would level.
Then measure and fit packers to put under the skid where the anchor bolt points are before tightening the anchor bolts down.
You need to workout a bolt tightening pattern to tighten down the anchor bolts but also you need a figure to tighten the bolts down to.
Finally adjust alignment of pump/motor etc. by using shims under the mounting feet.
I would suggest you contact the pump manufacturer and ask them about installation, I went on there website and found that they do manufacture and supply skids for applications like yours see the links below:-

http://www.yildizpompa.com/resim/metin/olculer.pdf

http://www.google.co.uk/imgres?imgu...aadMOyV0QX91YCABQ&sqi=2&ved=0CDoQ9QEwBA&dur=0

 

[bmw318be]

Yes Machined mounting pads on all equipment footing and this includes the machined flat for footing on the skid

So you follow cross torquing pattern on 1,4 and 2,3 for leveling.i believe motor sides 5,6 are the last leveling steps.

I think there is 2 nuts on the anchorbolt which 1 nut down is to hold up the frame

 

[desertfox]

Hi

Yep I think you might have a fighting chance, good luck

desertfox