Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations IDS on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Rack Sprinkler Balance Calc

Status
Not open for further replies.

Ehendrix

Mechanical
Nov 23, 2015
63
Has anyone used Hydracalc to perform a calc to balance the ceiling demand with the rack demand?

I am a little lost as to exactly how to make this work.

Thanks!
 
Replies continue below

Recommended for you

I am not familiar with that one. Not sure if it will do what you want.

Tmack is the man for that....
 
They have a little write up in the help area called dealing with multiple water supplies, support also confirmed that. Just trying to make sense of it and make it calc correctly.

Thanks,
 
It does it very easy. You just put all of the information in the calc program. Include your overhead and rack system together.

I often did it with 3 files. I had one that was the overhead only. 1 for the rack system only. Finally, one that was combined. You just copy/paste to put them together.

I did this so that I could better see what was happening with the racks and overhead. That way, I could make adjustments so that both systems were closer balanced at the common point. This would keep one from driving the other.

But, the process is very simple with all of the calculation programs out on the market today.

Travis Mack
MFP Design, LLC
"Follow" us at
 
I assume you don't have multiple water supplies. I assume you have a single supply that feeds a common distribution system that will serve an overhead riser and a rack system riser.

You can also do it where the rack come directly from the overhead. It is the same principle. When you meet the criteria in 13 for that, it is more common for the rack system to drive the overhead.

If you are lost in the logistics, give me a call. I haven't used HydraCADD in 15 years, but the process is still the same.

Travis Mack
MFP Design, LLC
"Follow" us at
 
Correct Travis I don't have multiple supplies only the pump and city water. Ok so I have calced each system separately that is done, so I will just save as and create another file and then copy and paste my rack calc into my main overhead calc.

I assume I only copy the rack sprinkler nodes and piping nodes that I am calculating up to the connection point of my overhead system?

So once I achieve that I guess my goal is to manually balance the calc so the safety margins are within .05psi of both calcs?

I've got the logistics, mostly it's just the process.

Thanks VERY much for the help!
 
The program will balance everything so that is taken care of. For example, if your rack system needs 90 psi and your overhead system needs 80 psi at the junction point, the computer will over-discharge the overhead system so that both are at 90 psi.

That is why I like to do them separately so that I can manually get them close. Then, let the computer handle the finer points of it.

For your other question, yes, copy/paste your rack system from the end heads back to your common point. The main file will have the piping from the common point back to the pump/city supply.

I have had systems where I have also used the pump for the overhead only and then had the balance point on the supply side of the pump. I did that because my pump was existing and it wasn't able to handle the combined flow of the overhead and racks.

Travis Mack
MFP Design, LLC
"Follow" us at
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor