Useful plumbing chart

[Jim Miller]

Found this from another poster on ReefCentral:

http://www.engineeringtoolbox.com/pvc-p ... d_801.html

Note the difference between a hard (normal) 90 elbow and a pair of 45s.

A flexible hose not kinked would be even better.

Makes a real case for avoiding 90 degree normal elbows if possible.

Jim

[fjf888]

4x the loss between 45 and 90 if I am reading the chart correctly, surprised it is so much different.

[Jim Miller]

Surprised me as well until I thought about it. Water doesn't know where it's going. Much of the water traveling into the elbow isn't at the nice roundy outside so it just hammers into the wall of the elbow perhaps buffered a bit by the stuff going around the nice roundy outside. Lots of turbulence results.

Do a similar thought process and see how the bounces occur on a 45 and you can see that the first bounce travels in a useful if somewhat turbulent direction in contrast to the 90's demolition derby.

Most folks look at the chart and see the number for the sweep 90 which usually isn't available at the big box stores. The "standard" 90 is what is commonly available unless your plumbing is big enough to use the sanitary sizes.

Flexpvc.com has sweeps in smaller sizes. Might be able to find them at dedicated plumbing supply houses as well.

I bought a roll of spaflex from flexpvc before I realized it's available at TruValue HW. Stupid me. Spaflex is nice because it is solvent welded just like normal PVC yet pretty flexible. So you get the flexiblity of hoses without dealing with hosebarbs and their restrictions.

Jim

[Jim Miller]

It's always interesting to read about folks who complain that their Cerges inline reactor made of a water filter housing kills the flow of their canister filter. Those things have at least four or five right angle bends internally and are often plumbed in the undertank area with at least two more.

Flow reduction is bound to occur.

jim