Seeking Mechanical Engineer for tank study

[Mike from Atlantic Beach]

Seeking Mech Engineer with subject matter experience to help study and verify design and mfg specs for a new scba tank that is 1/3 the size of standard tank but holds same volume of air. I am an investor that has been approached by designer and his patent attorney for investment. I seeking a expert to scrutinize and verify data.

Thanks,
Michael Hosto @ Gmail

www.linkedin.com/in/Michael-Hosto-96245b9

 

[grantctobin]

The math likely isn't super hard, but you'll likely find very poor buoyancy characteristics and an inability to fill to rated pressure (to ignore gas compressibility physics) and thusly poor adoption. Good luck w the search.

 

[Wookie]

Seeking Mech Engineer with subject matter experience to help study and verify design and mfg specs for a new scba tank that is 1/3 the size of standard tank but holds same volume of air. I am an investor that has been approached by designer and his patent attorney for investment. I seeking a expert to scrutinize and verify data.

Thanks,
Michael Hosto @ Gmail

www.linkedin.com/in/Michael-Hosto-96245b9

Mike

You might be interested in discussing with Mark Gresham from PSI.

PSI@psicylinders.com

I don't know if he is a Mechanical Engineer, but there isn't much he doesn't know about SCBA cylinders.

He is for hire, and will sign a NDE.

 

[broncobowsher]

They already exist. Hydrogen filling stations (few and far between) will regularly do 7500 PSI. And these cylinders are fitting into cars that are crash tested.

I remember seeing them offered at DEMA 6(?) years ago. They were working with a 3rd stage regulator to step the pressure down so a regular 1st stage scuba regulator.

There really isn't any science or new engineering in making high pressure cylinders. Getting them filled (affordably) is a huge hangup. It was a lot of work to step dive shops (and fire departments) from 2250PSI cylinders to 3000 PSI fills. Fire departments have gone a step further and are in the 4500 PSI range now. The fire departments are about mass. How much heavier must the cylinders be to support the higher pressure? Pretty sure the 4500 PSI carbon wrapped cylinders are right at the optimal point of a light enough cylinder and enough capacity.
I work with a guy what ran part of the California alternative fuel (hydrogen fuel cell). The cost to compress the gas to those pressures is the same as the fuel is worth. Basically doubles the price of the fuel.

You are doing research before investing. But you are researching the wrong data. The company you are looking at investing in has done it wrong. They created a solution to a problem that doesn't exist and are trying to justify it. They have you distracted with the math and engineering of the cylinders. Not the lack of a market for the product.

 

[Wookie]

The company you are looking at investing in has done it wrong. They created a solution to a problem that doesn't exist and are trying to justify it. They have you distracted with the math and engineering of the cylinders. Not the lack of a market for the product.

+1

SCBA packs are pretty much standard because the vast majority of SCBAs accept a certain sized cylinder.

If you make a cylinder of a different size, you have to convince the SCBA manufacturers to accept that different size. I don't know if SCBA cylinder sizes have ever changed, they are just made of different materials. Used to be 2250 PSI aluminum, then 3000 PSI aluminum, then 4500 PSI hoop wrapped. The practical limit of air compressor discharge pressure is 6000 PSI. Higher pressure compressors exist, but not for a reasonable price, and not easily obtainable by fire department service providers.

So now you have to design a new SCBA with a new regulator to handle much pressure and a new backpack to carry the new cylinder that is not backwards compatible with the old cylinders which are rated for an hour already. An hour. In a fire. You have to give your firefighter a break after the exertion of fighting a fire for an hour. Having been a volunteer firefighter in a former life, I'm here to tell you that if you're in a conflagration, an hour is an eternity.

I just don't see a market for a new style cylinder.

 

[rhwestfall]

@Luis H ?

 

[Manatee Diver]

Mike

You might be interested in discussing with Mark Gresham from PSI.

PSI@psicylinders.com

I don't know if he is a Mechanical Engineer, but there isn't much he doesn't know about SCBA cylinders.

He is for hire, and will sign a NDE.

I looked at his Linkedin and he has zero engineering background. Only formal education is a business degree and the USMC SGT program. And no real relevant experience where he would pick it up on the job.

 

[Johnoly]

I just don't see a market for a new style cylinder.

But the OP mentioned the size 1/3rd and he doesn't understand tanks as we all know them.

Given a 'the sniff/smell test' at 1/3rd the size........Would this then maybe be a mini-rebreather which would back up the OP's simplified verbage of the " Same Volume of air" ?? Cause the laws of physics sure doesn't smell right at 1/3rd.

 

[Luis H]

@Luis H ?

Hi Bob,

In general, I will have to agree with what @Wookie , @grantctobin , and @broncobowsher have said, but with the limited information from the OP, there are obviously some assumptions being made.

Maybe he already has a market, a very specific market or something…

He does say “scba” (not Scuba), so is he starting with a 4500 psi cylinder that he wants to reduce to 1/3 of its original size? Trying to compress air (not other gases) three times the present scba standard, I believe is a non-starter…

Creating a pressure vessel that can handle that pressure magnitude is not out of the question, but at first glance it doesn’t seem practical.

I would like to know a lot more details about the requirements and application, before I can make any specific comments...

 

[Luis H]

Mike

You might be interested in discussing with Mark Gresham from PSI.

PSI@psicylinders.com

I don't know if he is a Mechanical Engineer, but there isn't much he doesn't know about SCBA cylinders.

He is for hire, and will sign a NDE.

Mark Gresham is not an engineer. He is very knowledgeable, but I actually did some minor consulting for him years ago.