Low-Loss Liquid Fill- What Price Success?

Companies delivering liquid nitrogen, oxygen, and argon are fortunate these days to have some choices:

a) Pumped Systems- many of which have low transfer loss features

b) Pressure Driven Systems- some with MC-338 options allowing them to travel under pressure without venting between stops.

c) Pressure Driven Systems with Gas Use Capabilities- allowing them to be used not only for liquid delivery, but also for gas use for welding, purging, cutting, etc.

Which is best?

Of course- again we hit the millenium answer- It depends.

And it really does depend on what you are doing with the vessel- How much liquid you are delivering, what other uses (if any) you might have for the tank, and your budget.

The question crystallized after a client visit where it turns out they'd have been able to purchase two GOrilla 500s and a GOrilla 1500 (all tricked out with trailers) for what they paid for one low loss pumping truck. This is an irrelevant comparison where you need the pumping truck. Where you don't, it could be interesting to further explore where you get the most from your investment dollars.

Cryogenic Liquid Bulk Drops- Part III- Good for the Customer?

Having determined that bulk cryogenic convenience drops are usually a good thing for the vendor the question is “Are they good for the customer?” And, of course, comes the Millennium Answer: “It Depends.” So- what are the customer costs and benefits of convenience drops?

First- the potential negatives:

N-a) These drops are often commonly referred to as “dumps” where clients have a negative view. The biggest concern is that the liquid left in the transport is “hot” and will raise the temperature of the bulk tank receiving the product. In some cases a company is concerned that the transport has traveled from say Phoenix to Tucson to Albuquerque and back and now has 500 gallons they need to get rid of. When filling the delivery guy might blow down some of the pressure on the receiver of there might be a good deal of venting which could translate as wasted molecules. Or- the liquid did, in fact, heat the tank up a little it might cause product to boil off faster and there would be a net loss of product.

N-b) Most bulk agreements also include a “per delivery” fee and it is undesirable to be billed a delivery fee for partial drops.

N-c) There can occasionally also be logistics issues arising from getting a partial delivery on Tuesday when the regular delivery is Thursday resulting in less than a full drop on Thursday.

All these things can result higher total cost of goods.

And the potential positives:

P-a) A well placed client working closely enough with their supplier could see some significant cost savings if they are lucky enough to be strategic. This is especially true if the supplier is trying to expand into new territory and the client has a large enough tank to receive most of the excess product the transport might ever have. This could result in both good upfront pricing from the supplier and some waivers for delivery or other fees that significant reduce the total cost of liquid oxygen, nitrogen or argon.

P-b) A strong enough relationship (and big enough cryogenic bulk tank) could also almost eliminate the need for scheduling deliveries triggered by getting down to re-order levels.

P-c) And then there is the whole aspect of operating closely enough that “the right hand washes the left” where doing each other favors benefits both the supplier and client.
Jim Sherrow was one of my most influential members and he’d regularly point out that it is critical not to let the Aggravation Factor exceed the Incremental Dollar. Mostly he meant this as career counseling, but it also applies to relationships of convenience.

Golf as a Metaphor for Cryogenic Liquid Delivery

Are Bulk Cryogenic Spot Drops a Good Idea?

For the sake of collective sanity- Let’s agree that business profits are good and necessary. Bulk Cryogenic Liquid Suppliers have a number of challenges to overcome in order to turn a profit at the end of the day. Others will be explored over time, but one that is universal is transportation costs. One element of this is how many miles must be traveled to deliver a given quantity of liquid oxygen, nitrogen or argon. For more effort than most of us can imagine goes into trying to optimize this ratio.

Yesterday a good friend used a golf metaphor for business that applies. To wit- He wants his business to operate like a golf ball. When you hit a golf ball out there it stays out there and doesn’t come back. All returns are costly and one of the most important things that can be done with cryogenic liquid delivery is to be sure that all of the liquid that leaves the plant stays out.

One way that delivery companies help assure they are able to do this is to identify bulk tanks that can be used as field receivers for liquid that is left in a truck at the end of its route. So, for instance, a liquid nitrogen truck drives out to a suburb area and delivers 5200 gallons of its 6000 gallon load to clients. The 800 gallons that might be returned to the plant is now a liability. To avoid returning it, the driver might go to a client that did not call in for delivery, but has a 9000 gallon tank that always has some room in it and drop off his remaining liquid He now comes back empty and converted the 800 gallons he had from a cost to revenue.

Is this a good thing?

Did the revenue generated offset the cost of an 800 gallon delivery considering that Company X typically hates to deliver under 1500 gallons?

Is this a good thing for the client that received this drop?

Manana (later).

Temperature Effects on Gas Pressure

It is often hard to comprehend just how big an impact increased temperature can make of the gas pressure within a cryogenic liquid cylinder or bulk tank containing oxygen, nitrogen or argon.

My good friend Greg Cain at Oxylance provided the following information which is just slightly edited:

“One of the things that you may want to put in there to show people the gas volume / temperature is as follows.

Take a plastic bottle. The 1 liter size makes a bigger impression but a 16 or 20 oz will also work.

Get it warm and dry and put the top on it very tight. Stick it in the freezer for about 15 minutes and pull it out. As the air inside the bottle cools down the air molecules become smaller (more condensed) and the bottle will pull a vacuum on itself and when you take it out it will be half its normal size. The temperature difference will only be about 40 degrees (from 70 down to 30).

Now let the bottle warm back to room temperature by taking the lid off and get the bottle out to its normal size. Put the top on it tight and try squeezing it and see how soft it is. Remove the top and put the warm bottle and top back in the freezer. Leave it in there for 15 minutes. Reach in the freezer and put the top back on very tight and set it out in the sun. After it warms up try squeezing it and see how stiff the bottle is. A difference of 40 degrees will make the bottle so stiff you can’t squeeze it. Now think about how much difference it would make if you were going from -296 to +70 degrees.”

This last sentence is in reference to liquid nitrogen, oxygen or argon which have boiling points nearly 400 degrees F from what we consider to be room temperature.

Thanks, Greg!

Cryogenic Liquid Cylinders- Safe Lifting Method

A few weeks ago we discussed some of the potential hazards and risks associated with lifting liquid cylinders to elevated locations along with ways not to lift them. It is agreed among all manufacturers that the handling ring around the top of a liquid cylinder is not to be used as a lifting point. While some instruction manuals show cryogenic liquid cylinders being lifted by the holes in the handling ring support brackets this is not a universally recommended practice. This is especially true regarding full cylinders being lifted overhead. The risk of lifting any liquid argon, oxygen or nitrogen vgls by the support brackets are that:

a) It is unlikely if you know the specific cylinder you are lifting is one with supports designed for lifting;
b) The liquid cylinder supports could have been weakened over time by being bent and straightened or through metal fatigue or corrosion.

In any case- the support brackets can tear away from the vessel allowing it to drop. A liquid cylinder full of product that is dropped from an overhead location is a clear hazard.

So- What are the options?

1) Consider running feed lines up from your vessel to the work area first and keeping all liquid containers at ground level;
2) If the distance from the ground to a work area is prohibitively long then use a safe carrier to raise the vessel to the area needed.

A photograph of an enclosed carrier for lifting liquid cylinders is shown. These can also be fitted with lifting eyes on all four corners for 4-point lifting. Be sure that whatever you use that the device is regularly inspected for damage or corrosion and that any lifting cables are in-spec for the intended purpose.

West Cryogenics Manufactures New Cryogenic Equipment in the U.S.

Yes. West Cryogenics manufactures brand new GOrilla & Ultra Cryogenic Liquid Oxygen, Nitrogen and Argon Tanks and Dragon Vaporizers in their ASME Code plant in Willis, Texas. And- clients are welcome to come and watch the manufacturing work being done. You can see everything from welding nozzles on heads and then welding the heads to shells and performing ASME pressure tests to seeing how super-insulation wrapping is done and vessels are sealed and mass-spec tested to be sure they are leak free. Then you can see the heated and cool vacuum processing, sand blasting, painting, and piping…… not to mention also getting to see cleaning materials for oxygen service and performing tests and analyses.

When you really think about it this ranks with touring the Blue Bell Ice Cream and Dr. Pepper plants except that manufacturing brand new cryogenic vessels in the United States is a lot less common than ice cream or soda pop. I have to say this in a very qualified manner, though, because it is a bit of an understatement to refer to Blue Bell simply as “ice cream” or Dr. Pepper as “soda pop.” It is more likely that they, in fact, are the very real modern personification of “milk and honey.” And well, you know, GOrilla Tanks, Ultra Tanks, and Dragon Vaporizers are mighty fine, too. And- They are all manufactured new in the U.S.