Class 200 PVC Pipe Sizing Guide
Using this chart will tell you how many gallons to run inside of Class 200 PVC pipe. This is the most common pipe irrigators use. Most people believe its schedule 40 pipe used for sprinklers, but its actually class 200.
Following this chart, if you wanted to run 75 GPM (Gallons Per Minute) through class 200 pipe you’d look on the left and find that there. You’ll see that we must use 1 1/4” pipe for that many gallons.
But say our heads are using 3.0 GPM each. After we use that size pipe to plumb in four heads, we’re down to 63 GPM. Now we can reduce down to a 1” pipe size, and so on. This increases velocity as you move to the last head vs keeping the same size all the way down.
