Is turbocohen still onthis Forum?

[PPINZ]

thread71-293823
I see last input was 2011. A lot of movement with propane as a motor fuel in USA.
We are building aluminium propane tanks and have been seeing many steel tanks with huge issues with rust etc internally.
Wondering if there has been any improvement with fuel quality/standards with all these new players in the market?
Thanks

 

[MikeHalloran]

I wouldn't call this progress:

http://www.theguardian.com/world/2013/jul/30/explosions-florida-propane-plant

I don't think a root cause has been determined or mentioned, but Blue Rhino is in the business of selling recycled, refilled propane tanks, so corrosion should be of interest to them.


Not coincidentally, I have noticed that "20 pound" propane tanks (which are now sold with something like 13 pounds of product inside) have gotten much, much lighter (tare weight) over the last couple of decades. They are now very similar (unbelievably thin) to the similarly sized single-use non-refillable-by-law tanks in which wholesale refrigerant is sold.


How much corrosion allowance do you build into your aluminum tanks?



Mike Halloran
Pembroke Pines, FL, USA

 

[turbocohen]

Who is Turbocohen and what is he doing on this forum? Arrest that man.

 

[franzh]

The reason most exchange cylinder companies are selling cylinders with less total product is they have little control over how or where the cylinder is stored. A properly filled 20 lb cylinder could expand to 100% full if allowed to overheat in a garage or other enclosure. The easy way to minimize the liability is to reduce the amount of product. That amount is clearly stated on the label. Now, as for cylinder being thinner, I havent seen any and fully dont expect to. DOT engineering code specifies the cylinders design which includes pressures and weight limits.

Back to the OP. Rust has been a problem with steel cylinders but not widespread. Some do, most dont. Rust cannot form once a cylinder enters service as there is no oxygen to promote the formation. Any rust would be the result of the cylinder being opened prior to service and allowing oxygen and moisture to enter.

US Autogas quality standards have not improved in many years and its long overdue. This is a self assigned task I am pushing for. Lets hope it gets some attention.

Now, as to who and where is Turbo? That rascal!

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[Compositepro]

The reason the propane companies only put 15 lbs. of product in a 20 lb. tank is to make more profit. The tanks already have over fill protection devices to prevent filling more than 80%, which gives the tanks a 20 lb. capacity. The government sued the industry for doing it secretly. Now they state the 15 lb. net weight in very small print on the label. Of course, most consumers have no idea that a full tank holds 20 lbs. Where I am I can get a refill of 20 lbs. for about $13.50 or get an exchange with 15 lbs. for $18-$24.
Exchanges are prolifferating because the retailer does not need to have trained and licensed employees and extra insurance.

 

[Tekton]

In recent years there has been talk of inferior quality LP-Gas being substituted, with subsequent performance and durability losses to auto engines

Presumably however it still falls within established API automobile standards - - ?

What brands if any retain the original specifications?

Is this an issue throughout U.S.A. and Canada?


Tekton

 

[berkshire]

Tekton,
Can you elaborate on this, I am using propane to power outboard motors, and would like to know of any potential problems before I encounter them. I already know about wax deposits.
B.E.

You are judged not by what you know, but by what you can do.

 

[franzh]

Tek, most LP distribution pulls from common pipelines with the distribution closest to a particular refinery or gas plant having a higher concentration of either a desirable or less desirable product. No company to my knowledge is knowingly selling an inferior product, it would be harder to get than a standard product. Even though HD-5 is the national minimum standard, that still allows for a wide range of "other products" in the fuel. Unless the fuel blend is specifically requested at the refinery and a very strict protocol on the transportation chain, the retailer may be getting LP from a dozen different facilities with little actual knowledge of a particular shipments origination.

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Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[berkshire]

Composite pro,
You are describing good old American profiteering, it really has not changed, since the days of John Davison Rockefeller.
B.E.

You are judged not by what you know, but by what you can do.

 

[Compositepro]

I do not fault companies for maximizing profits. I was primarily correcting the statement about the safety issue. But the short-filling of tanks can only occur if consumers are too ignorant/stupid/lazy to care. I was also trying to pass on information so others are aware (less ignorant). When consumers feel they have plenty of money they do not care that much about price so prices will rise to a point where they start to care (the lazy issue). I'd best not say anything about the stupidity of consumers.

 

[PPINZ]

Had interesting discussion with a chap when I was last in the US. he was an engineer with one of the big 3. He said 'some' propane is stored in old salt mines?
This is why some corrosion in some parts of the country and not others.
One tank I had a look inside with a camera had sheets of rust falling off inside - like it had been at sea for years.
The outside looked like new.
Another big issue is the particulates found in the fuel, causing issue to fuel pumps etc.
The graph I was shown showed they needed filtration down to 2 microns to catch the little sods.
Many believe including myself that with the huge increase we are starting to see with propane powered vehicles that a tighter quality control standard needs to be implemented.
Berkshire, what systems are you running on your outboards? injection/ vapour, liquid?

 

[berkshire]

PPINZ
They are vapour systems, using a modified carb, and a boiler running off the cooling water to ensure vapour is delivered to the carb.

Composite pro.
I am well aware of the Blue rhino / Amerigas cylinder swap issues. The only thing they did around here, was to make the short weight label bigger.
My local jobber was selling at 2.99 per gallon until last week then they jumped to 3.49 citing some state tax increase.
B.E.

You are judged not by what you know, but by what you can do.