Plumbing 90 or 45

yetiman · 10/30/2007, 01:02 PM

When plumbing your supply and return lines is it better to use 2 45's instead of one 90? I would think the 2 45's would allow for a more gradual transition. Thanks

kgross · 10/30/2007, 01:29 PM

The simplest thing to do is use 1 or 2 sizes larger pumbing than you think you need. Then the friction loss of the elbows/45's/T's etc will not make any noticable difference. If you don't want to upgrade your pumbing size and you are still worried about the 2 45's verses one 90. Normally the 2 45's will create slightly more friction loss than the single 90. It is not the actual fitting that causes the increase in friction. It is the increased number of changes in the plumbing. When you go from pipe to a fitting, there is a change is size, which creates turbulance and friction. When you have 2 45's you have 4 changes, with a 90, you only have 2. The 45's do create less friction loss, but the increase in turbulance, increases the friction loss more than the decrease from the 45s. To test this out use the head loss calculator on the RC home page.

KIm

IPT · 10/31/2007, 01:19 AM

So, then my idea to splice segments of Spa Flex (which has a curve to it) with varying degrees of roation with couplers creating the bends I need without using 45's is self defeating? Dang...

kgross · 10/31/2007, 11:41 AM

Just use the spa flex in a larger size and skip all of the connectors other than at each end and you will get max flow from your plumbing setup.

kim

10/30/2007, 01:02 PM	#1
yetiman Registered Member Join Date: Sep 2004 Location: Oshkosh WI Posts: 239	Plumbing 90 or 45 When plumbing your supply and return lines is it better to use 2 45's instead of one 90? I would think the 2 45's would allow for a more gradual transition. Thanks

10/30/2007, 01:29 PM	#2
kgross Premium Member Join Date: Nov 1999 Location: Nampa, ID Posts: 5,870	The simplest thing to do is use 1 or 2 sizes larger pumbing than you think you need. Then the friction loss of the elbows/45's/T's etc will not make any noticable difference. If you don't want to upgrade your pumbing size and you are still worried about the 2 45's verses one 90. Normally the 2 45's will create slightly more friction loss than the single 90. It is not the actual fitting that causes the increase in friction. It is the increased number of changes in the plumbing. When you go from pipe to a fitting, there is a change is size, which creates turbulance and friction. When you have 2 45's you have 4 changes, with a 90, you only have 2. The 45's do create less friction loss, but the increase in turbulance, increases the friction loss more than the decrease from the 45s. To test this out use the head loss calculator on the RC home page. KIm __________________ Proud Member of the Idaho Marine Aquarium Society America will only be the Land of the Free as long as it is the Home of the Brave. Current Tank Info: AGA 180gallon tank, VHO/MH lighting, DSB, calcium reactor, Also a 7 Gallon Nano softy tank, and a 32 gallon cube

10/31/2007, 11:41 AM	#4
kgross Premium Member Join Date: Nov 1999 Location: Nampa, ID Posts: 5,870	Just use the spa flex in a larger size and skip all of the connectors other than at each end and you will get max flow from your plumbing setup. kim __________________ Proud Member of the Idaho Marine Aquarium Society America will only be the Land of the Free as long as it is the Home of the Brave. Current Tank Info: AGA 180gallon tank, VHO/MH lighting, DSB, calcium reactor, Also a 7 Gallon Nano softy tank, and a 32 gallon cube

10/31/2007, 01:19 AM	#3
IPT Registered Member Join Date: Feb 2007 Location: Alaska Posts: 3,197	So, then my idea to splice segments of Spa Flex (which has a curve to it) with varying degrees of roation with couplers creating the bends I need without using 45's is self defeating? Dang...