How to join 2 well pump pipes? 4

[chipomatic]

I have been requested to replace a 10" x 8" tee in a water supply system with a wye. The tee is the point where two 10" lines that each come from a drinking water supply well that is pumping water to a treatment plant come together. From the tee, the water flows to the plant via the 8" line.

We have worked up a design for the lines to join a little further downstream at a 10" 45 degree angle wye, then reduce to the 8" a little further downstream. I was wondering if anyone has any ideas that should also be incorporated. Apparently it is not an option to have only one of these well pumps running at a time and this wye configuration is to improve the flow characteristics at the point that the 2 lines join. Thanks.

 

[cvg]

this will reduce your head loss a bit, but not likely to make a huge difference. Sounds like your 8 inch line should be upsized to 10 inch line all the way to the plant.

 

[chadl]

Perhaps I am missing something here, but it sounds like you are taking two 10 inch supply lines from your well pumps and combining them into a single 8 inch line to feed your treatment plant. This seems strange as you would typically combine two smaller supply lines into a larger one, not a smaller one, particularly if both well pumps can operate at the same time. If I'm understanding you correctly either your two 10 inch supply lines are grossly oversized, or your 8 inch line is grossly undersized. Is this a short length of 8 inch to the plant? Remember, flow rate is porpotional to the square of the diameter, so your two 10 inch lines can (at the same velocity) carry over 3 times as much water as the single 8 inch line (or conversly, the velocity in your 8 inch line will be 3 times that of your 10 inch lines resulting in significantly more head loss). Combining the two 10 inch feeds into a single 14" line would represent a more balanced design. Again all this assumes the 10 inch lines from the well are properly sized

Chad

 

[STYMIEDPIPER]

WHY ARE YOU REPLACING THE TEE??
Did the tee fail or are you attempting to correct a flow issue??
If you are replacing the tee due to flow issues than you need to adhere to the advise of the other responses and review the entire distribution piping.
Do not use a 'band-aid' approach for a potentially much larger problem.
The problem may be that the initial engineering was suspect. It has happen!!