Pump casting broken 2

[srisua]

Dear seniors

I have erected a positive displacement pump along with piping in one of our project. after completion of erection of piping we have observed a crack at pump discharge flange. Photographs of the same attached herewith. My customer is saying that this is happened due to mismatch of piping. I said that this much crack will not develop even pipe line alignment is not good, vibration can be developed. I am presuming that this crack developed due to defects in pump body casting. Request all of you to suggest what could be the reason?

http://files.engineering.com/getfil...1b9-aae13e157bd3&file=IMG-20150923-WA0008.jpg

http://files.engineering.com/getfil...213-487fd8b302ef&file=IMG-20150923-WA0006.jpg

Regards

 

[desertfox]

Unfortunately I doubt that it is a flaw in the pump casing, it is more likely an installation problem particularly now has you have indicated that no particular bolt torque as been used or by the sounds of it a bolt tightening sequence.
I should have also asked what alignment tools were used to align the pump/motor etc.
If I were your client I would not accept flaws in the casting without some proof and that would mean sending it to a laboratory for analysis.

“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein

 

[Artisi]

Think you are sticking your neck out will be standing alone taking the track of faulty casting.
Better to hold your tongue until you have undertaken a proper investigation and review of the failure.

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.)

 

[srisua]

Kind attn: Mr. Desertfox

Dear Sir,

Pump and motor alignment done by pump manufacturer, not by us. Total assembly of pump and motor is mounted on foundation and proper grouted with special cement by us. I am also agreeing that it could be the reason of misalignment. meanwhile I am suspecting defects in casting. As you said, proper analysis to be done for casting for which request you to suggest me whether chemical analysis and mechanical properties are sufficient or any other tests are required.

Kind attn: Mr. Artisi

Dear Sir,

Your suggestion is well taken and request you to suggest me the investigation about casting.

Regards

 

[desertfox]

Hi

You would need to send the failed parts to a laboratory to undergo analysis by a metallurgist who would be able to detect flaws under a microscope. If pump alignment has been done by pump manufacturer then they should be contacted and asked to explain how the pump and motor was aligned and also ask them what they think caused the failure.
If the pump was provided by client then he should be contacting the pump supplier regarding the problem.

“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein

 

[srisua]

Mr. Desertfox

Thank you very much and will be done accordingly

Regards

 

[Artisi]

Everyone is getting too far ahead, first step is to carefully unbolt the inlet and discharge pipework from the pump flanges, don't charge in like a bull at a gate thinking that it is a casting failure - carefully and mindfully dismantle the pipework from the pump and observe if the pipe alignment is / was the problem -----

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.)

 

[bimr]

Regarding "Yes, as you said there might be undue stress due to inadequate pipe supports. I am also suspecting casting defects in pump. I dont feel thermal expansion between day and night temperatures as in India, at the moment maximum 30 degC and minimum is 20 deg C."


The empty pipe temperature may be much higher than 30 DegC when the pipe is exposed to the sun, probably as high as 68 DegC.

 

[gempump]

Obviously,I promise this is an installation problem.

Heavy-Duty Centrifugal Slurry Pump Manufacturer

http://www.gempump.com