Idea! related to air pump system

[gabdewulf]

What if the air lines had 45 degree connections instead of 90?

See the ms paint masterpiece for the visual

So looking at code for water line, they want 45 angles to reduce the pressure on the bends in pipes. My working theory is the air will spread more evenly throughout the room not having those 90. Thereby, no slow down/weak pressure at the end of the line. Plus, I guess, less pressure on the pipes.

 

Thoughts?

[Fish Folk]

Not sure exactly what you’re envisioning, but I don’t think it would make much difference. The main issue is the power of your source pump. If that’s strong enough, everything generally follows well.

[gabdewulf]

It's a theory that hoping someone has tested...because I don't want to buy the air pressure gauges to check. But the sharp bends may make the whole setup less efficient, in theory, based on the various videos including the a co-op video where the far end wasn't enough to power a egg air stir pump. 

 

My needed length of pipe is longer than what the hardware store sells which is 10+ft. I would to get joiners anyways to keep them straight at 10+ ft length so going to try with the 45 bends for the last ft or two in the corner.

[JettsPapa]

Assuming that would help with the air pressure, which I very much doubt, I don't think it would be enough to justify the need for the extra material you'll be using (two 45° fittings and a short piece of pipe at each corner instead of one 90° fitting).  Plus, more joints means more places that can come apart or start leaking.

[gabdewulf]

Actually, instead of 4 x 90 degree elbows and 4 joiners to reach the full 12ishft square system I'm building, the system will be 10 ft and 2 ft pipes with 8 x 45 degree elbow. Material cost isn't much different. For some reason, the big box stores around me only sell pipe in 10ft streches instead of 12ft streches.

[JettsPapa]

On 7/16/2024 at 1:41 PM, gabdewulf said:

. . . For some reason, the big box stores around me only sell pipe in 10ft streches instead of 12ft streches.

As far as I know pipe has always been sold in 10' or 20' pieces (although I believe some oil field pipe is 21').

[Tony s]

I'm not sure the 45's make a difference for airflow. Running water I could see causing a small difference. All I can say...  we run lines for household and building water, airlines for air compressors, liquid lines for liquid fat, and high-pressure lines for pressure washers. I don't think we've ever put in a 45 before in 50 years

[gabdewulf]

On 7/16/2024 at 4:09 PM, Tony s said:

I'm not sure the 45's make a difference for airflow. Running water I could see causing a small difference. All I can say...  we run lines for household and building water, airlines for air compressors, liquid lines for liquid fat, and high-pressure lines for pressure washers. I don't think we've ever put in a 45 before in 50 years

That's weird because our local Code requires 45s for drainage.

[Tony s]

On 7/16/2024 at 7:27 PM, gabdewulf said:

That's weird because our local Code requires 45s for drainage.

Well about that... I don't have local codes😁. or didn't used to anyway. about 20 years ago the county hired its first building inspector. up until then houses didn't even need inspected. unless the local city had its own codes. which I know nothing about. and I believe dwv systems are designed with 45's integrated into the fittings

[Tony s]

@gabdewulf my apologies for that first post. It came off a little strong. Not my intention at all. I often post while at work. And apparently I was getting annoyed with my machinery at that point. I could see that working for water. It’s a bit of an odd code. Or older code. Most modern plumbing is usually pex at this point. We used cpvc when we built the house. There may be 2 45’s in the house and those were accommodate the subfloor layout. In the livestock buildings, there are no 45’s. And flow is fine. I think it all depends on what kind of flow it has. And several of those buildings have a constant flow rate of 50 gpm 
 

air is a bit different. There is no frictional stress. And any turbulence shouldn’t really do much. Unlike water. So it’s more dependent on the pressure than the pipe fittings. If you keep the pressure constant, it won’t make any difference what the fitting is. It’s not really pushing any different from spot to spot. More important would be the actual diameter of the pipe. It creates a larger reservoir of air to draw from. Making constant pressure easier to maintain. 

[Odd Duck]

On 7/16/2024 at 6:27 PM, gabdewulf said:

That's weird because our local Code requires 45s for drainage.

Probably because it relies on gravity vs pump pressure.  Drainage isn’t a pressurized system, typically, unless you have to pump up from a basement and then it only pumps up to a certain height until it can then gravity feed into the sewer.

As @Tony s said, air doesn’t have the friction issues of water in our relatively low pressure systems so 45 vs 90 just isn’t an issue.  If you want 45’s for an aesthetic reason, or you need it to fit your space, by all means.  It isn’t necessary when an air loop is used.  It could be necessary if you’re under-powered.  If you have enough pressure, to slightly over what you need (ideal), you should have an air bleed so you don’t have too much back pressure on your air pump over the long haul.  You would want a gauge, ideally, so you know what your pressure is running.

Edited July 18 by Odd Duck
Typos

[JettsPapa]

On 7/16/2024 at 6:27 PM, gabdewulf said:

That's weird because our local Code requires 45s for drainage.

Drainage isn't under pressure, so clogs are more likely at 90's as opposed to 45's.

[gabdewulf]

Yeah, I get the no local codes. 20+ years ago I was a builder in Mississippi and the only thing they cared about was framing wood spaces due to hurricanes...and even then the inspector never checked.

 

All good points on friction and gravity.

 

I got one of the co-op air pistons and the first time messing with one, so maybe over researching the whole topic. 

[Pepere]

On 7/13/2024 at 9:55 AM, gabdewulf said:

So looking at code for water line, they want 45 angles to reduce the pressure on the bends in pipes. My working theory is the air will spread more evenly throughout the room not having those 90. Thereby, no slow down/weak pressure at the end of the line. Plus, I guess, less pressure on the pipes.

First of all, given that it is a loop, there is no end, just a far corner…

Second, As pipe is much bigger than air hose, there is precious little velocity of air going down the pipe, hence minimal frictional losses…

Third water is dramatically more viscous than air.  Consider for example a sailboat.  The sails above the water are dramatically larger than the underwater wings, (keel and rudder)  the keel and rudder balance the force of the wind on the sails…  the fact you are moving air in the pipe vs water greatly reduces the relative losses.

 

as a general rule, a 90 degree bend imposes the same flow restriction as adding 3 feet of pipe  2 45s would impose a bit less flow restriction than a single 90, but iirc, it doesnt cut the restriction in half…

 

 

 

I dont think it would be worth the bother…