Any engineers here that can help with this? Please?

[Texashiker]

As long as I don't stamp any documents and put a disclaimer I should be safe 😀

I have an idea of the specs, just want a second opinion.

The I-bream is going to have reinforcement gussets at load bearing points.

Everything is going to have 1/4 - 5/16 fillet welds.

I am thinking about using 6 inch I-beam

I used to work as a welder in a structural shop.

 

[Fern]

Damn, that seems like a lot expense and trouble. I would just buy a portable gas/diesel generator and be done with it.

A generator also gives the added of benefit of being able to use you electrical appliances when there's a power outage. I live in the mountains where there are occasional outages, we all just use generators.

Fern

 

[Texashiker]

Damn, that seems like a lot expense and trouble. I would just buy a portable gas/diesel generator and be done with it.

Yes, it is a lot of work.

But when the power goes off, I will have 400 - 500 gallons of water. There will be a spigot on the outside of the tank so we can get water with absolutely no water.

I have a coleman gas powered generator, that would be my primary backup.

 

[Fern]

Yes, it is a lot of work.

But when the power goes off, I will have 400 - 500 gallons of water. There will be a spigot on the outside of the tank so we can get water with absolutely no water.

I have a coleman gas powered generator, that would be my primary backup.

I don't understand.

I'm on a well. If the power goes out all I need for unlimited water is a generator sufficient to start my well pump.

If you already have a generator I don't see the need for a water tower.

What am I missing here?

Fern

 

[Texashiker]

I'm on a well. If the power goes out all I need for unlimited water is a generator sufficient to start my well pump.

You are limited by the amount of fuel you have.

Pump #1 will probably be submersible. To get water into the tank the generator will be running that pump.

Pump #2 is between the storage tank and the home.

When the power goes out, how can I reduce the amount of fuel needed to supply water? By raising the tank off the ground and letting gravity do the work hopefully we can eliminate the need for a second pump in times of emergency. Or, as was suggested use a 12 volt RV pump.

~ EDIT ~

This is what we use at the deer camp. the elevated tower provides enough water to wash hands, flush toilet, have hot water,,, with only gravity.

 

[Fern]

You are limited by the amount of fuel you have.

Pump #1 will probably be submersible. To get water into the tank the generator will be running that pump.

Pump #2 is between the storage tank and the home.

When the power goes out, how can I reduce the amount of fuel needed to supply water? By raising the tank off the ground and letting gravity do the work hopefully we can eliminate the need for a second pump in times of emergency. Or, as was suggested use a 12 volt RV pump.

~ EDIT ~

This is what we use at the deer camp. the elevated tower provides enough water to wash hands, flush toilet, have hot water,,, with only gravity.

I think I understand. It sounds like you're concerned there will be no gas stations with power near enough to you to buy more fuel. I guess that happens in hurricanes (outages covering a large area). Over here, our outages come from ice/storms and downed trees taking out power lines. Some gas station, somewhere, will still have power. A different problem I suppose.

Fern

 

[Texashiker]

I think I understand. It sounds like you're concerned there will be no gas stations with power near enough to you to buy more fuel.

Something like that, yes.

After hurricane Rita a few years ago, my family and I were without power for 18 days. We had to drive close to 45 miles to get fuel for the generator.

 

[Fenixgoon]

I'm yet another engineer that can't help you... this time metallurgical/materials

And as such I demand to know what material you're using for your tank.

woohoo, another metallurgist!

i'm actually like 50% materials (metals, high strength steels) and 50% (experimental) fracture mechanics. i like the structural side of things too.

not sure about wind resistance, but i imagine the primary driver for sizing the tower legs would be buckling (stiffness controlled) and possibly bending moments from wind forces.

i could make a few first order estimates, but they'd all be *very* first order 😀

 

[the DRIZZLE]

Something like that, yes.

After hurricane Rita a few years ago, my family and I were without power for 18 days. We had to drive close to 45 miles to get fuel for the generator.

First of all, pumping the water up to the tank takes exactly the same amount of energy as pumping it to an equivalent PSI so you aren't saving anything. Second, the amount of energy required to lift 500 gallons of water 30 feet in the air is much less than a gallon of gas even accounting for all the inefficiencies in system.

If want to minimize the generator run time in an emergency you can either put in a larger pressure tank or get some 12v batteries and an inverter, or a second 12v pump for emergency use.

 

[ussfletcher]

I'm a computer engineer, you should have used python.

 

[iGas]

I'm not a structural engineer but I did stay at a Holiday Inn last night...

I am however a chemical engineer so I can answer the question on height. If you aren't going to utilize a booster pump, you will need to have ~140 feet from the top of the water in the tank to the point of use. I've found that 60 psi is what you get out of a typical home faucet.

See if you can buy a certified plan for constructing such a water tower. I feel that would be a better idea.

Default pressure switch on a pressure tank for a well water system is 40/60 PSI, but most if not all faucets including shower should function just fine at 30 PSI or greater pressure.

30 PSI / 0.43 PSI per foot = 69.77 feet

That mean the bottom of your water tank must be at least 70 feet higher than the highest fixture in your house to have adequate pressure for use. Unless you employ booster pump.

It would make more sense to install a booster pump with pressure switch.

 

[William Gaatjes]

Nope🙁.

People have sued successfully over "professional opinions". If you imply (worse if you really are?) that you have specialized knowledge in a field and give some advice vocally with no writing, there may be grounds for a lawsuit if something goes wrong.

And a contract has to be two-way and agreed upon for that disclaimer to work.

That is truly insane, but to be expected in the US or Canada.

Common sense :
If you do not have a contract, it is your responsibility, not the person that gives the advice. It is your responsibility to check if the advice that you are receiving is valid. If you cannot do that, hire a professional and create and sign a contract. Do not blame another giving advice for the fact that you do not know.

 

[thejunglegod]

Bernoulli's explains it well. I should explain just in case. You've got three terms there, pressure energy, kinetic energy, and potential energy. Basically at the top of the tank you have zero kinetic energy, zero pressure energy (assumed exposed to atmosphere), and a lot of potential energy. At the bottom of the tank(grade) you have zero potential energy, and if you assume zero kinetic energy, you have a lot of pressure energy. If you go through it you can derive the P=(H*SG)/2.31

This Pressure is not pressure at a particular point but the Differential pressure between the high & low pressure points , thus enabling you to gauge the level of water inside the tank - the basic principle for level transmitters.
What you've mentioned is the maximum pressure at the lowest point inside the tank. However, if we add the pressure head from the lowest point in the tank to the lowest point at the faucet/shower head, that would give you the accurate pressure head at a particular point.

So, P = (H+h)*SG,
where H = height of water column inside the tank
& h = distance between the lowest point in the tank to the faucet/shower head.

Ohh, and i don't know shit about Construction btw, so OP I cannot help you there. If you want info on gauges to warn you about low/high level of water in the tank, then do let me know.

 

[CLite]

I want to build a homemade water tower.

Tank specs:
Capacity: 550 Gallons
Dimensions: 67" dia. x 44"H
Weight: 99 lbs.

That is just for the tank, and not the frame.

What size I beam does the frame need to be made out of to support the tank when full? I am certified ASME section 8 pressure vessel and heat exchanger code welder. All welding will be done with ES70 flux core.

How wide does the base need to be to withstand 130 mile per hour winds? I live in a hurricane prone area.

How high off the ground does the base of the tower need to be to supply water pressure to a home?

Support bars on the side to prevent the tank from tipping.

Basic diagram, may not be to scale.

There really is no reason to do a wide base, get some sturdy beams, plung them into concrete pillars, although you may need to use some kind of sacrificial galvanic protection system for the portion of the beam in concrete(I'm not as familiar with corrosion protection).

For wind design you will need to use ASCE-7, I'm traveling so I don't have a copy with me but I have a mathcad with it implemented. In a hurricane zone ASCE-7 would have you use 150mph and when combined with a couple factors it results in a wind pressure load of 216 lb/ft^2. 67in diameter x 44 height would be a net load of 216*67*44/144 = 4,422 lb. This is a pretty conservative number, if I had ASCE-7 in-front of me I could probably lower the prediction by using coefficients more appropriate for your setup.

You can compare the 4,422 lb to shear limits of beams in AISC and then depending on height (F * Height) compared the resulting moment to moment limits of beams in AISC. A decent structural engineer could probably tell you off the top of his/her head what an appropriate i-beam would be for such a load. Search junk-yards/etc. and just find whatever is cheapest that meets the minimum requirement. The weight of the water would be very easily supported by any beam that can resist overturning moment due to a hurricane.

Finally since you can't weld your plastic tank to the restraint bars, I'd wrap a couple wires going from one side over the top to the other side to prevent it from being lifted out of it's craddle if it gets hit with high winds when empty.

*edit* forgot to mention I'd go with a 3 pillar design

 

[deadlyapp]

This Pressure is not pressure at a particular point but the Differential pressure between the high & low pressure points , thus enabling you to gauge the level of water inside the tank - the basic principle for level transmitters.
What you've mentioned is the maximum pressure at the lowest point inside the tank. However, if we add the pressure head from the lowest point in the tank to the lowest point at the faucet/shower head, that would give you the accurate pressure head at a particular point.

So, P = (H+h)*SG,
where H = height of water column inside the tank
& h = distance between the lowest point in the tank to the faucet/shower head.

Ohh, and i don't know shit about Construction btw, so OP I cannot help you there. If you want info on gauges to warn you about low/high level of water in the tank, then do let me know.

Agreed, I went to grade simply because the 2~6 feet for a faucet or shower head will be relatively negligible in the broad scheme of things, especially if we aren't taking into account losses through the pipes and fittings.

 

[Imp]

That is truly insane, but to be expected in the US or Canada.

Common sense :
If you do not have a contract, it is your responsibility, not the person that gives the advice. It is your responsibility to check if the advice that you are receiving is valid. If you cannot do that, hire a professional and create and sign a contract. Do not blame another giving advice for the fact that you do not know.

You know what, I think I mixed up the disclaimer part. There was a case where an engineer protected himself from a third-party that he did not have a direct contract with. So, yes, you can cover your ass with a disclaimer... but all the court cases I've studied have been between actual companies/parties where the professional doled out "official" professional advice where there was a working relationship.

The "professional opinion" thing is another matter. You "may" be sued if the judge/jury thinks all the details work out, so do be more careful about dishing out "professional" advice even if you think it's casual is the take-away.

Best example is you talk to a doctor on the street, and he thinks you have or don't have a disease, then end up getting sick cause he/she is wrong. I'd be pissed and who knows who I'd think about suing if I were pissed.

 

[alkemyst]

Have you checked your local code first for the legality of both a structure of that size and one that contains water?

Both can be potential issues to your neighbors.

 

[Slew Foot]

I'm not an engineer but I lol at the person who wants to build a 140 foot tower to hold two tons of water in theirhurricane backyard in hurricane country

 

[NikolaeVarius]

I'm not an engineer but I lol at the person who wants to build a 140 foot tower to hold two tons of water in theirhurricane backyard in hurricane country

Redneck Engineering. Just needs more duct tape.

 

[Slew Foot]

You know what, I think I mixed up the disclaimer part. There was a case where an engineer protected himself from a third-party that he did not have a direct contract with. So, yes, you can cover your ass with a disclaimer... but all the court cases I've studied have been between actual companies/parties where the professional doled out "official" professional advice where there was a working relationship.

The "professional opinion" thing is another matter. You "may" be sued if the judge/jury thinks all the details work out, so do be more careful about dishing out "professional" advice even if you think it's casual is the take-away.

Best example is you talk to a doctor on the street, and he thinks you have or don't have a disease, then end up getting sick cause he/she is wrong. I'd be pissed and who knows who I'd think about suing if I were pissed.

That's actually not true for medicine. You need to have a working relationship with the physician for a recommendations to be legally valid. Talking to someone on the street doesn't constitute a relationship.

 

[kevinsbane]

You know what, I think I mixed up the disclaimer part. There was a case where an engineer protected himself from a third-party that he did not have a direct contract with. So, yes, you can cover your ass with a disclaimer... but all the court cases I've studied have been between actual companies/parties where the professional doled out "official" professional advice where there was a working relationship.

The "professional opinion" thing is another matter. You "may" be sued if the judge/jury thinks all the details work out, so do be more careful about dishing out "professional" advice even if you think it's casual is the take-away.

Best example is you talk to a doctor on the street, and he thinks you have or don't have a disease, then end up getting sick cause he/she is wrong. I'd be pissed and who knows who I'd think about suing if I were pissed.

There have been civil cases where an engineer has been found liable for the (friendly) engineering advice given to a neighbour. There is an expectation of professional conduct given that someone knows you are an engineer and can depend on that advice, and therefore you are liable if you give such advice.

The professional organizations that govern engineering in (Ontario, anyways) uphold the profession of engineering as a bastion of technical and professional knowledge. Thus, if we want people to look up to engineers as having this sort of special status, our advice given must also have that special status; that is, having the backing of the authority of our profession.

In Ontario, if something goes wrong, even in the absence of a contract, even if the civil case works itself out and you're not found liable, the Professional Engineers of Ontario will censure you for professional misconduct and may impose a number of different penalties.

Essentially, if someone knows you're an engineer (of the appropriate field), and you give them advice pertaining to that field, treat it as if you are liable for that advice.

 

[disappoint]

Build a series of towers using thicker and thicker material until they no longer collapse under the weight. Then double the size of the structural members and call it a day.

That's how people learned to build things before we had to worry about stuff like "math" and "physics".

 

[Imp]

That's actually not true for medicine. You need to have a working relationship with the physician for a recommendations to be legally valid. Talking to someone on the street doesn't constitute a relationship.

Not true?

http://www.ama-assn.org/amednews/2006/03/13/prca0313.htm

Consulting with a patient outside the exam room in an informal setting in no way lessens your legal liability. And since one of the best ways to protect yourself from liability is through documentation, an undocumented, casual exchange between you and your patient could lead to trouble. The level of risk, of course, is higher if the person who has approached you is already your patient, because a physician-patient relationship has clearly been established.

It is that type of parking lot conversation between a physician and patient that is at the center of a medical malpractice lawsuit filed late last year against a New York cardiovascular specialist.

According to the complaint filed in the state Supreme Court in Riverhead, N.Y., in Suffolk County, 67-year-old Herbert O'Rourke died seven days after an undocumented consultation with his physician of 20 years, Hachiro Nakamura, MD.

There have been civil cases where an engineer has been found liable for the (friendly) engineering advice given to a neighbour. There is an expectation of professional conduct given that someone knows you are an engineer and can depend on that advice, and therefore you are liable if you give such advice.

The professional organizations that govern engineering in (Ontario, anyways) uphold the profession of engineering as a bastion of technical and professional knowledge. Thus, if we want people to look up to engineers as having this sort of special status, our advice given must also have that special status; that is, having the backing of the authority of our profession.

In Ontario, if something goes wrong, even in the absence of a contract, even if the civil case works itself out and you're not found liable, the Professional Engineers of Ontario will censure you for professional misconduct and may impose a number of different penalties.

Essentially, if someone knows you're an engineer (of the appropriate field), and you give them advice pertaining to that field, treat it as if you are liable for that advice.

Well, that covers it a hundred times better than I can. Currently half-assed studying for my PPE exam. Totally going through the motions, and I learned more from my engineering law grad course than the books/answers I'm trying to read.

 

[William Gaatjes]

You know what, I think I mixed up the disclaimer part. There was a case where an engineer protected himself from a third-party that he did not have a direct contract with. So, yes, you can cover your ass with a disclaimer... but all the court cases I've studied have been between actual companies/parties where the professional doled out "official" professional advice where there was a working relationship.

The "professional opinion" thing is another matter. You "may" be sued if the judge/jury thinks all the details work out, so do be more careful about dishing out "professional" advice even if you think it's casual is the take-away.

Best example is you talk to a doctor on the street, and he thinks you have or don't have a disease, then end up getting sick cause he/she is wrong. I'd be pissed and who knows who I'd think about suing if I were pissed.

I understand, but i still find it bizarre. With the doctor example is one flaw : The doctor should make use of the scientific method. A doctor may share an opinion, ok. But a doctor should always make use of examination to give a proper diagnosis. I would find it strange and wrong if a judge would condemn a doctor for giving an opinion on the street without an examination and that the doctor also did advise to see a specialist for a proper examination because that doctor could only give an estimation. I agree if some quack would give a diagnosis without proper procedure of examination, then that doctor is indeed liable. But you as a patient are also responsible for understanding that a doctor must examine you in order to give a proper diagnosis. And you as a patient should always check for a second opinion when in doubt.

 

[gorobei]

First of all, pumping the water up to the tank takes exactly the same amount of energy as pumping it to an equivalent PSI so you aren't saving anything. Second, the amount of energy required to lift 500 gallons of water 30 feet in the air is much less than a gallon of gas even accounting for all the inefficiencies in system.

not true.

water towers for NY city type apartments use large tanks on the roof on a trickle flow from a relatively smaller diameter pipe than the main lines to each apt. the flow is 24/7 at way lower pressure than the faucet/tap because people only need say 60 gal at 40psi for 15min(say taking a shower). the tank can replace an equivalent amount of water at much lower pressure because it runs continuously and runs overnight(say 10 psi for 10 hours while the occupant is at work or sleeping).

you dont need a pump capable of 40 psi if your tank is high enough. therefore the energy use can be less if it is lower pressure and runs for longer. i would think even a smaller end solar rig could manage a low pressure pump.