orientalexpress
Guest
note to myself ,don't mess with Vince.my mother toll me never mess with a guy that know to made Bomb 
peace
lapsan
peace
lapsan
Calcium Reactors and Pressure
- Thread starter iani
- Start date
orientalexpress
Guest
oh btw,don't you guys work?get off the computers
lapsan
lapsan
Vincerama2
Supporting Member
[quote author=orientalexpress link=topic=5970.msg75940#msg75940 date=1232485674]
note to myself ,don't mess with Vince.my mother toll me never mess with a guy that know to made Bomb
peace
lapsan
[/quote]
You mean a guy who can make flares. Sulfur, Potassium Nitrate, Carbon (crushed charcoal or sugar). I found the "recipe" in a dictionary under "gunpowder". (Nowadays wikipedia has an entry)
You'd get a much bigger bang from firecrackers you buy in Chinatown!
Anyway, back to the topic on hand, I hope the CA reactor works!
V
note to myself ,don't mess with Vince.my mother toll me never mess with a guy that know to made Bomb
peace
lapsan
[/quote]
You mean a guy who can make flares. Sulfur, Potassium Nitrate, Carbon (crushed charcoal or sugar). I found the "recipe" in a dictionary under "gunpowder". (Nowadays wikipedia has an entry)
You'd get a much bigger bang from firecrackers you buy in Chinatown!
Anyway, back to the topic on hand, I hope the CA reactor works!
V
G
GreshamH
Guest
[quote author=pixelpixi link=topic=5970.msg75530#msg75530 date=1232349680]
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
Vincerama2
Supporting Member
[quote author=GreshamH link=topic=5970.msg76137#msg76137 date=1232576336]
[quote author=pixelpixi link=topic=5970.msg75530#msg75530 date=1232349680]
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
Come to think of it, I've been lazy and shut off the valve between my return pump and the return line and NOT unplugged the pump while doing a water change. I'm pretty sure my return pump is stronger than a maxijet, and the return pump didn't detonate the vinyl return hose, or even pop it loose from the pumps hose barb fitting.
V
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
[/quote]
[quote author=pixelpixi link=topic=5970.msg75530#msg75530 date=1232349680]
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
Come to think of it, I've been lazy and shut off the valve between my return pump and the return line and NOT unplugged the pump while doing a water change. I'm pretty sure my return pump is stronger than a maxijet, and the return pump didn't detonate the vinyl return hose, or even pop it loose from the pumps hose barb fitting.
V
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
[/quote]
iani
Supporting Member
[quote author=GreshamH link=topic=5970.msg76137#msg76137 date=1232576336]
[quote author=pixelpixi link=topic=5970.msg75530#msg75530 date=1232349680]
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
[/quote]
So why did a lot of the BAR DIY reactors crack?
[quote author=pixelpixi link=topic=5970.msg75530#msg75530 date=1232349680]
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
[/quote]
So why did a lot of the BAR DIY reactors crack?
Gomer
Guest
I work with a lot of possitive and negative pressures. The first question which comes to mind is: For the bar DIY reactor, what was the pressure inside the vessel? What is the pressure in a typical pressurized vessel. All is speculation until this is known.
Trivial pressure can cause a design flaw to crack. Not saying it is a design flaw, but it is also a possibility.
Trivial pressure can cause a design flaw to crack. Not saying it is a design flaw, but it is also a possibility.
pixelpixi
Guest
That's not correct at all. 1 psi is equivalent to approximately 27.4 inches of head pressure. So if a maxi-jet could produce 20 psi then it would be able to pump to a height of 46 feet. It clearly can't. In fact, a maxi-jet 400 is listed as having a maximum pumping height of 29". So it's about 1psi.
Furthermore, when you restrict the outlet of a pump it does not increase the pressure. If water is moving through the restriction, the pressure will be lower. If water is not moving, the pressure on both sides will be identical.
Furthermore, when you restrict the outlet of a pump it does not increase the pressure. If water is moving through the restriction, the pressure will be lower. If water is not moving, the pressure on both sides will be identical.
iani
Supporting Member
My original 15-20 psi is way off lol. However if you use this equation and constrict your output to 1/8" tubing the PSI at the end is still quite high.
Converting head in feet to pressure in psi
Pump curves in feet of head can be converted to pressure - psi - by the expression:
p = 0.434 h SG (1)
where
p = pressure (psi)
h = head (ft)
SG = specific gravity
Say you constrict your pump from 1/2inch tubing to 1/8" tubing. Doesn't your pump head increase 16 times?
Converting head in feet to pressure in psi
Pump curves in feet of head can be converted to pressure - psi - by the expression:
p = 0.434 h SG (1)
where
p = pressure (psi)
h = head (ft)
SG = specific gravity
Say you constrict your pump from 1/2inch tubing to 1/8" tubing. Doesn't your pump head increase 16 times?
pixelpixi
Guest
That's the same formula in different units. Using your formula:
p = .434 * (27.4 inches/12.0 inches per foot) * 1.025 = 1.02 psi
[quote author=iani link=topic=5970.msg76212#msg76212 date=1232599965]
Say you constrict your pump from 1/2inch tubing to 1/8" tubing. Doesn't your pump head increase 16 times?
[/quote]
It absolutely does not. The pump head remains exactly the same. Try taking a small pump with two different types of tubing and raise the end of the tubing up until it stops pumping water. That height will be the same regardless of the size of the tubing.
p = .434 * (27.4 inches/12.0 inches per foot) * 1.025 = 1.02 psi
[quote author=iani link=topic=5970.msg76212#msg76212 date=1232599965]
Say you constrict your pump from 1/2inch tubing to 1/8" tubing. Doesn't your pump head increase 16 times?
[/quote]
It absolutely does not. The pump head remains exactly the same. Try taking a small pump with two different types of tubing and raise the end of the tubing up until it stops pumping water. That height will be the same regardless of the size of the tubing.
iani
Supporting Member
[quote author=pixelpixi link=topic=5970.msg76222#msg76222 date=1232600779]
It absolutely does not. The pump head remains exactly the same. Try taking a small pump with two different types of tubing and raise the end of the tubing up until it stops pumping water. That height will be the same regardless of the size of the tubing.
[/quote]
Erin that makes no sense. The reason there is a max head of a pump is because of the weight of the water its pushing up the tubing. If the smaller tubing is 1/16 of the volume of the bigger tubing it should be able to push the water up the tubing 16 times. Which is why high pressure pumps always have smaller outputs than the equivalent low pressure pump.
It absolutely does not. The pump head remains exactly the same. Try taking a small pump with two different types of tubing and raise the end of the tubing up until it stops pumping water. That height will be the same regardless of the size of the tubing.
[/quote]
Erin that makes no sense. The reason there is a max head of a pump is because of the weight of the water its pushing up the tubing. If the smaller tubing is 1/16 of the volume of the bigger tubing it should be able to push the water up the tubing 16 times. Which is why high pressure pumps always have smaller outputs than the equivalent low pressure pump.
pixelpixi
Guest
It's because the pressure is the weight of the water per square inch of cross section. The larger tubing holds 16 times more water, but it has a 16 times larger cross section.
Think about this: The world has 361 million square kilometers of ocean. If the width of a column of water had an effect on pressure at a given depth, then the pressure a foot under the ocean's surface would be billions of PSI.
If you're still not convinced, try it! Hook up a small pump to two different pieces of tubing and see how high each piece of tubing has to be for it to stall out. I'll bet you $100 it's the same!
Think about this: The world has 361 million square kilometers of ocean. If the width of a column of water had an effect on pressure at a given depth, then the pressure a foot under the ocean's surface would be billions of PSI.
If you're still not convinced, try it! Hook up a small pump to two different pieces of tubing and see how high each piece of tubing has to be for it to stall out. I'll bet you $100 it's the same!
iani
Supporting Member
You would owe me 100. That is simply not correct. The diameter of tubing is inversely related to the velocity of the water. Velocity is directly related to PSI (velocity = PSI x 2.307). Therefore PSI is also inversely related to the diameter of tubing. PSI would increase when decreasing the diameter of tubing. When PSI increases the pump max head increases per what was already discussed.
Gomer
Guest
Two things
1) head pressure isn't mass. It is mass over area. If you go to a 3ft diameter tube you still pump to the same height, but the change in water level vertically is much much slower. Imagine something odd: Take a 5ft vertical hose. It takes X pressure to be able to fill water to the top. Now imagine 2ft hose, connected to a 1ft cube container connected to another 2 foot tube. The amount of pressure required to fill to the top is the same*. It doesn't matter that there is that big box of water.
2*) Conductance. When you shrink the aspect ratio severely, the pressure scales faster than the surface area. This is fluid flow mechanics. When the sufrace area of the wall becomes large compared to the volume it contains, you really need to start worrying about frictional forces.
1) head pressure isn't mass. It is mass over area. If you go to a 3ft diameter tube you still pump to the same height, but the change in water level vertically is much much slower. Imagine something odd: Take a 5ft vertical hose. It takes X pressure to be able to fill water to the top. Now imagine 2ft hose, connected to a 1ft cube container connected to another 2 foot tube. The amount of pressure required to fill to the top is the same*. It doesn't matter that there is that big box of water.
2*) Conductance. When you shrink the aspect ratio severely, the pressure scales faster than the surface area. This is fluid flow mechanics. When the sufrace area of the wall becomes large compared to the volume it contains, you really need to start worrying about frictional forces.
iani
Supporting Member
[quote author=Gomer link=topic=5970.msg76242#msg76242 date=1232604010]
Two things
1) head pressure isn't mass. It is mass over area. If you go to a 3ft diameter tube you still pump to the same height, but the change in water level vertically is much much slower. Imagine something odd: Take a 5ft vertical hose. It takes X pressure to be able to fill water to the top. Now imagine 2ft hose, connected to a 1ft cube container connected to another 2 foot tube. The amount of pressure required to fill to the top is the same*. It doesn't matter that there is that big box of water.
2*) Conductance. When you shrink the aspect ratio severely, the pressure scales faster than the surface area. This is fluid flow mechanics. When the sufrace area of the wall becomes large compared to the volume it contains, you really need to start worrying about frictional forces.
[/quote]
Huh? But doesn't the PSI change with a smaller diameter tubing?
Two things
1) head pressure isn't mass. It is mass over area. If you go to a 3ft diameter tube you still pump to the same height, but the change in water level vertically is much much slower. Imagine something odd: Take a 5ft vertical hose. It takes X pressure to be able to fill water to the top. Now imagine 2ft hose, connected to a 1ft cube container connected to another 2 foot tube. The amount of pressure required to fill to the top is the same*. It doesn't matter that there is that big box of water.
2*) Conductance. When you shrink the aspect ratio severely, the pressure scales faster than the surface area. This is fluid flow mechanics. When the sufrace area of the wall becomes large compared to the volume it contains, you really need to start worrying about frictional forces.
[/quote]
Huh? But doesn't the PSI change with a smaller diameter tubing?
G
GreshamH
Guest
[quote author=iani link=topic=6024.msg76160#msg76160 date=1232588238]
[quote author=GreshamH link=topic=5970.msg76137#msg76137 date=1232576336]
[quote author=pixelpixi link=topic=5970.msg75530#msg75530 date=1232349680]
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
[/quote]
So why did a lot of the BAR DIY reactors crack?
[/quote][quote author=iani link=topic=6024.msg76160#msg76160 date=1232588238]
[quote author=GreshamH link=topic=5970.msg76137#msg76137 date=1232576336]
[quote author=pixelpixi link=topic=5970.msg75530#msg75530 date=1232349680]
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
[/quote]
So why did a lot of the BAR DIY reactors crack?
[/quote]
Construction mainly. We paid very little attention to gluing in proper temps, not stressing the plastic during cutting, etc. It's not the same as pressure breaking it. It takes far more PSI to crack acrylic and trust me, you'll never get 60 psi out of a MJ as you'd blow the tiny o-ring FAR before it ever hitting 60psi :lol:
[quote author=GreshamH link=topic=5970.msg76137#msg76137 date=1232576336]
[quote author=pixelpixi link=topic=5970.msg75530#msg75530 date=1232349680]
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
[/quote]
So why did a lot of the BAR DIY reactors crack?
[/quote][quote author=iani link=topic=6024.msg76160#msg76160 date=1232588238]
[quote author=GreshamH link=topic=5970.msg76137#msg76137 date=1232576336]
[quote author=pixelpixi link=topic=5970.msg75530#msg75530 date=1232349680]
I just don't buy it. I think the only way you'd get high pressures is if you closed off both the intake and effluent and let the CO2 run. I'm planning to set it up with a valve on one or the other, but not both, so that should never occur.
[/quote]
I don't buy it either, not even for an extra $100 on top of it. This is the first I have ever heard about such a thing and I agree re: low pressure pump couldn't pump against a pressurized vassal. Not to mention the drip rate would change from a drip to a stream prior to a unit being able to crack or blown up. The change would be noticeable in the tank IMO. Most likely they are cracking as they used extruded and poor craftsmanship (using alcohol on extruded, etc)
[/quote]
So why did a lot of the BAR DIY reactors crack?
[/quote]
Construction mainly. We paid very little attention to gluing in proper temps, not stressing the plastic during cutting, etc. It's not the same as pressure breaking it. It takes far more PSI to crack acrylic and trust me, you'll never get 60 psi out of a MJ as you'd blow the tiny o-ring FAR before it ever hitting 60psi :lol: