Getting Choked by PVC

peppie · 05/17/2013, 09:22 PM

Had a small plumbing project in the garage today.
I am surprised that we get any flow out of theses fittings.
A dremal tool and a few mins of work and you to can make a difference.

Looks like I almost doubled the hole diameter.

Will this make a big difference? or am I splitting hairs?
This is the difference between the thin wall and regular PVC

nemosworld · 05/17/2013, 10:09 PM

You basically made thin wall PVC which they already make and sell in lowes and Home Depot. Not sure what will gain from what you did though.

bnumair · 05/17/2013, 10:30 PM

thin wall is sch 40 pipe and thick wall is sch 80. the only difference is wall thickness and pressure rating. i have used both in my setups and i just dont find a need for sch 80 thick wall pvc at all in our tanks.
i dont think it will make much of a difference in flow either way.

looks like ur working with 1" pipe and its rated for 3510 gph max with a pump while 960 gph gravity fed.

peppie · 05/17/2013, 10:44 PM

Both pipes are sch 40. One is thin wall one is regular thickness. Neither are sch 80.
I beg to differ on the flow results by reshaping the inside of that T I feel I will gain something. Maybe not so much on the straight pipe.

silverwolf72 · 05/18/2013, 02:55 AM

It comes down to head pressure and how well your pump handles it.
A larger inside diameter and less obstructions the less head pressure will be and the more flow you can get of the pump.

sleepydoc · 05/18/2013, 12:33 PM

A Much easier and better way to accomplish the same thing would be to go up a size with your PVC (and switch to Sch 40 from sch 80 if you're using that.)

The wall thickness of schedule 40 PVC in sizes we use is on the order of 0.11-0.15" so any increase gained by reaming out the inside will be minimal. For long lengths of pipe you will only be able to ream out a bit at the end. for other fittings, you run the risk of reducing the strength and compromising the integrity of the fitting - doubly important since fittings tend to have more stress on them.

On top of these issues is the fact that although the diameter may be marginally increased, the edges are significantly roughened which will increase turbulence and resistance to flow at the edge, so the net gain in flow is questionable.

jerpa · 05/18/2013, 12:36 PM

DWV pipe and fittings have a larger I.D. They also have sweep 45's and 90's. Their pressure rating is more than sufficient for our systems.

05/17/2013, 09:22 PM	#1
peppie Registered Member Join Date: Oct 2009 Posts: 1,883	Getting Choked by PVC Had a small plumbing project in the garage today. I am surprised that we get any flow out of theses fittings. A dremal tool and a few mins of work and you to can make a difference. Looks like I almost doubled the hole diameter. Will this make a big difference? or am I splitting hairs? This is the difference between the thin wall and regular PVC

05/17/2013, 10:09 PM	#2
nemosworld Registered Member Join Date: Oct 2009 Location: Houston TX Posts: 1,411	You basically made thin wall PVC which they already make and sell in lowes and Home Depot. Not sure what will gain from what you did though. __________________ Felix Nice to meet you! Current Tank Info: 60 Gallon Cube

05/17/2013, 10:30 PM	#3
bnumair Dr. Reef at ur service Join Date: May 2009 Location: Tulsa, Ok, USA Posts: 7,751 Blog Entries: 15	thin wall is sch 40 pipe and thick wall is sch 80. the only difference is wall thickness and pressure rating. i have used both in my setups and i just dont find a need for sch 80 thick wall pvc at all in our tanks. i dont think it will make much of a difference in flow either way. looks like ur working with 1" pipe and its rated for 3510 gph max with a pump while 960 gph gravity fed. __________________ Water Quality: NO3 0,Phos 0,Cal 440,Alk 7.5,Mag 1300 "Reef Fast, You Crash, Reef Slow, You Pass" Mike's Reef 3:16 Current Tank Info: 350g DT,95g sump, 50g Frag tank, 4800gph return 4x Sea swirls. 6x AI Vega Color. 200# Pukani rock, dual recirculating skimmer, Biopellet, GFO Carbon rx's, Cal rx. Closed loop. 1.5hp chiller, genesis renew. Apex & RKE

05/18/2013, 12:33 PM	#6
sleepydoc Registered Member Join Date: Oct 2011 Location: Minneapolis, MN Posts: 3,907	A Much easier and better way to accomplish the same thing would be to go up a size with your PVC (and switch to Sch 40 from sch 80 if you're using that.) The wall thickness of schedule 40 PVC in sizes we use is on the order of 0.11-0.15" so any increase gained by reaming out the inside will be minimal. For long lengths of pipe you will only be able to ream out a bit at the end. for other fittings, you run the risk of reducing the strength and compromising the integrity of the fitting - doubly important since fittings tend to have more stress on them. On top of these issues is the fact that although the diameter may be marginally increased, the edges are significantly roughened which will increase turbulence and resistance to flow at the edge, so the net gain in flow is questionable. __________________ ~~~~~~~~~~~~~~~~~~~~~ 120 gallon, coast to coast overflow w/beananimal overflow. Waveline DC 10000 II return pump, 40 gal sump, Octopus XS200 skimmer, T5 lighting

05/18/2013, 12:36 PM	#7
jerpa Registered Member Join Date: Apr 2011 Location: Pittsburgh Posts: 2,174	DWV pipe and fittings have a larger I.D. They also have sweep 45's and 90's. Their pressure rating is more than sufficient for our systems. __________________ Jer Current Tank Info: 40b basement sump, 40b refugium, 30g frag

05/17/2013, 10:44 PM	#4
peppie Registered Member Join Date: Oct 2009 Posts: 1,883	Both pipes are sch 40. One is thin wall one is regular thickness. Neither are sch 80. I beg to differ on the flow results by reshaping the inside of that T I feel I will gain something. Maybe not so much on the straight pipe.

05/18/2013, 02:55 AM	#5
silverwolf72 Registered Member Join Date: Jul 2005 Location: Lake Forrest CA Posts: 1,732	It comes down to head pressure and how well your pump handles it. A larger inside diameter and less obstructions the less head pressure will be and the more flow you can get of the pump.