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Safe level lifting of pipes during flushing or blowing

Safe level lifting of pipes during flushing or blowing

Safe level lifting of pipes during flushing or blowing

(OP)
Hi, I am asked a question from construction the following:

1. How much elevation they can lift the installed pipe from its shoes or stand during flushing if required. The pipes are carbon steel and are 3 to 6 inch in size. Length is about 50 meters. is there a calcualtion to prove how safe etc

2. Similarily they want to spread the flange connection using flange spreader and same question is coming up how safe it is spread the flange beyond 1 inch ... is there any calculation please..
Thanks !  

RE: Safe level lifting of pipes during flushing or blowing

If I understand your question right, they (the test group ?) want to lift (with a crane ?) one or more 50 meter long pipes (that are filled with water/other fluid) "up" so the pipes will drain?

Hint: how many supports are in place (per real design!) to hold up those pipes now?  How far apart are those supports?   How do "they" propose supporting the lifted pipe equally so it doesn't break the flanges and connections, nor deflect the pipe?      

RE: Safe level lifting of pipes during flushing or blowing

Maybe something like dividing the span by 180 or even 360 could give you some kind of reasonable answer, but that would still always depend on how close to pressure limits the pipe is operating at the time, the wall thickness and steel grade.  Its better to develop some rules of thumb for some particular data set.  There are many grades of carbon steel and wall thicknesses of pipe, both of which affect the answer you're looking for.   

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

RE: Safe level lifting of pipes during flushing or blowing

(OP)
Thanks to both Racook and Biginch. Yes- "they" means people doing flushing. I understood we should support it while on lifting by crane if they are doing so by crane.

Big inch,  I, think I understood what you meant. For time being I take that deviding it by 360 is ok. So biginch, should I take for for 50 meters, we can lift it by an elevation of 5000mm/360= which is  13mm approx without any support? - can you comment?

Thanks a lot

RE: Safe level lifting of pipes during flushing or blowing

If you do the math right, that would be 138 mm.

My comment said and implied that you might be able to develop a guideline using criteria such as a deflection limitation based on span length and an appropriate divisor, maybe 180 or 360, or some similar real positive integer number, which you should determine based on what is safe for your piping diameter, wall thickness and grades, and consider an additional dynamic load factor for tugging from the lift block machinery too.  I specifically did not say that you would be able to lift a 50 meter section, or any other length of your pipe by L/360 without breaking it.

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

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