Cryogenic Fill Hose Safety Reliefs- An absolute necessity

Why are safety reliefs installed on all cryogenic liquid oxygen, nitrogen, argon or carbon dioxide fill hoses?

In fact- safeties are not only to be installed on all fill hoses. They are also installed on any cryogenic line that is sealed on both sides. This is because cryogenic liquid trapped in a line will vaporize and expand exponentially creating tremendous pressure in hoses, piping or tubing. This expanding liquid nitrogen, oxygen, argon, or CO2 can easily build enough pressure to cause the line or hose to explode with great force.

This is a danger that is easily overlooked and one that is not obvious to someone without prior knowledge or training. And- it is something that can be missed by even the most experienced personnel who are hooking up a new line out of necessity or otherwise in a hurry.

Whether you are filling medical oxygen bases, transfilling liquid from one DOT4L vessel to another or otherwise filling from a bulk source it is essential to have a relief for expanding vapor. So- never forget to be sure the hose you are using to fill has a properly rated safety relief installed somewhere between the valves or other connectinos that could trap liquid.

Adversity Liberates new GOrilla 1500

A post from a few weeks ago discussed "the liberating force of adversity" and the paradox of great innovation in difficult times. This week's release of the new West Cryogenics 1500 gallon GOrilla is another prime example. While this vessel has been on the books for development a long while now there was a major challenge in trying to work the design in between so many competing priorities.

Well- get a little break from the mad rush of things and see what you get......

Once again, West Cryogenics has managed to innovate at a level not regularly matched. The new GOrilla will include all the standard features found on the existing 500 gallon and 850 gallon GOrilla portable cryogenic vessels:

- Combo Top Bottom Fill

- Robust Pressure Building System

- Road Relief Valve Allowing for Liquid Transport

- Gas Output with Economizer and External Vaporizer

It will also have an auxillary 2" liquid withdrawal line for those who want to add pumping systems for liquid delivery. Rated at 250psi mawp this vessel will afford flexibility to serve both gas feed and liquid delivery systems for liquid oxygen, nitrogen or argon. And- it can be paired up with its smaller 290 to 500 gallon cousins, cryogenic liquid cylinders or gas cylinders for an almost unlimited variety of Hospital and Medical Emergency Backup and Rapid Deployment applications or fitted with mixers for direct distribution of blended welding gases.

No- West Cryogenics does not enjoy economic downturns at all. But- once again- a little downturn has provided a great opportunity for innovative development.

There has been a tradition of using downtime to come out even stronger for the future and no one at West Cryogenics can see a reason to break that tradition this time.

Simple Set Screw Solution- Shrink Seal

Today’s suggestion: Shrink Seal the set screws on your cryogenic liquid cylinder pressure building and economizer regulators.

There has been a lot of emphasis in this post on the difference between flow and pressure. The primary focus of discussion has been to try and clarify the fact that higher pressure does not equate to higher flow. Point: Cranking up the pressure builder setting on your liquid oxygen, nitrogen or argon 4L-DOT liquid cylinders does little or nothing to provide higher flow and can cause a number of negatives……..

- Out of Balance Economizers,
- Broken PB Regulators,
- Excessive Venting and more.

Solution- Leave the set screw alone. The odds of this happening- It depends.

Make it harder to mess with the screw and you might find an ounce of prevention to be worth a pound of cure. Where necessary- Create consequences for tampering with pressure builders and you might deter even more tinkering.

Oh, and yes- West Cryogenics has been doing this for years and sells both shrink seal material and heat guns.

www.westcryogenics.com

Progress Paradox

“And I must say: I find the liberating power of adversity to be one of the more disquieting facts of life.”
- John H. Lienhard

In Episode 1603 of The Engines of Our Ingenuity, Lienhard discusses the adverse life, imprisonment, and great grief of Galileo. It seems that absent the opportunity provided by Galileo’s isolation he might never have performed his world changing work that has done so much to shape modern engineering, material science and astronomy. And, Lienhard’s writing as well as numerous other texts, such as “Selling Soap. Literally” in this month’s Fast Company, go a long way to show how adversity can spawn innovation.

West Cryogenics’ move into manufacturing is a case in point. Long interested in developing and producing new products, the company was always “too busy” to move forward in this area. The downturn following the 9/11 tragedy and some other unexpected turns created a unique moment where time, talent and market converged allowing for development of West’s Ultra Series liquid delivery vessels. The follow up development of GOrilla portable cryogenic vessels and packaged systems along with Dragon vaporizers has now positioned West Cryogenics as a nationally recognized manufacturer of quality solutions for cryogenic liquid argon, oxygen and nitrogen delivery and gas use systems.

T. Boone Pickens’ writing introduced me to the phrase “It’s root hog or die.” And that is often the case. Current rooting is leading to the development of several new product lines, systems, and relationships that will not only sustain through tough times, but also create opportunities to thrive in times of plenty.

None of us wish for tough times to make us better and the fact they can is indeed disquieting. It is also a reassurance for those who have stared into the abyss and found inspiration, innovation and purpose that we might otherwise have been too busy to see.

A Better Fix for Less?

A client called this morning inquiring about current pricing for 350psi (4L-292) cryogenic liquid cylinders (VGLs) and said his customer’s are requesting them instead of the 235psi (4L-200) VGLs he has been providing. Interestingly enough, he was also requesting repairs on six of his liquid cylinders with a note to be sure and check the pressure builders.

Possibility: End users have been cranking down on the pressure builders of his liquid cylinders to try and get more flow out of them.

The rub is that the flow from a DOT 4L-200 or a 4L-292 is just almost identical (+/- 300scfh depending on the model and whether you are vaporizing liquid oxygen, nitrogen or argon). So, higher pressure will not make higher flow. What will provide extra flow is to add some downstream vaporization allowing for a doubling or more of the gas withdrawal rate.

Suggestion: Put a hang-on Vap on the liquid cylinder at a cost of around $1000 to $2000. This is:

a) a lot less expensive than purchasing six new higher pressure liquid cylinders at $2000 to $3000 each;
b) actually better since it solves the problem which the new liquid cylinders would not;
c) and keeps the existing liquid cylinders in service and generating revenue.

Granted- this is assuming that the real issue is flow. We discussed visiting with the customer first to get a better idea of their application. There are just so many more applications that run at 80 to 110psi versus over 200psi means that it is likely they really don’t need 350psi liquid cylinders.


Pay a lot less and get what you really need? Hmmm.........

Road Valves for Portable Cryogenic Vessels

“Road Valves” were mentioned in the last article without defining them. A Road Valve consists of a 25psi or less relief device and an isolation valve installed as a bypass to the main safety relief on a portable cryogenic vessel. The purpose of this bypass system is to assure that pressure does not exceed 25psi while the vessel is transporting cryogenic liquid oxygen, nitrogen or argon over the road. The 25 psi mark is noted in the DOT exception found in 49CFR 173.320 and also outlined in specific exemptions established for a variety of cryogenic transports and portable vessels.

Compliance with the applicable exception or exemption typically requires that the vessel pressure be maintained at a level below 25.3 psi so most valves are set at 22-24psi for added assurance. It is the responsibility of the transporting driver to vent the vessel down below 25psi and open the road relief isolation valve prior to traveling with contents. Not all portable cryogenic vessels are fitted with road valves. For instance- Those built under DOT-4L or MC-338 specifications are typically able to travel at their full operating pressure.

The critical point here is that it is very important to understand the applicable guidelines and legalities for transporting cryogenic liquids with whatever vessel you are using. Ignorance of the law is no defense and fines related to DOT violations can be enormous. Most importantly- the guidelines were established not only for the safety of the operator, but also for those around them.

NOT PORTABLE- Skid Mounted Vertical Cryogenic Tanks.

What do you say when someone asks you to install a Road Valve on a vertical cryogenic bulk tank that is mounted on a fork pocket style palletized base and designed for stationary use only?

No.

There are tanks that are made to hold liquid for stationary applications only and are, in turn, not suitable for transporting cryogenic liquids. Many small vertical bulk tanks are now being fitted with fork pocket bases because it makes them so easy to move to a new installation site and set in place. In many applications the base also serves as the pad for the tank to support the legs. They also allow for pre-plumbing of final line manifolds and vaporizers. But- your typical 300 gallon or larger vertical cryogenic bulk tank is not made to be moved with liquid in it which is the common differentiator for “portable.”

True portable tanks are typically horizontal vessels that are built under DOT specs, exemption or exception and are designed to be moved full of liquid. Putting a base on a stationary tank does not make it all of the sudden qualified to be portable. And putting a Road Valve on a liquid oxygen, nitrogen or oxygen tank designed specifically for stationary use does not make it legal for transporting cryogenic liquids.

Granted- There are vertical vessels that are designed for transporting liquid including your typical DOT 4L cryogenic liquid cylinders and some of the micro-bulk vessels that are larger than the DOT 4L class. But- only certain specifically designed and classified vessels are for liquid transport. And the manufacturers of these vessels justifiably charge more for them so they provide very clear information on those vessels that are designed for transport.

There is significant risk associated with moving stationary-only vessels that are full of cryogenic liquids. Hazards include injury caused by tipping and turning over forklifts or other handling equipment. Inner vessel supports on stationary vessels are also not made to sustain movement of full vessels creating a lot of potential for damage to equipment and personnel. Stationary micro bulk vessels not designed for movement with liquid are regularly seen with broken neck tubes and other damage caused by someone improperly moving them full of liquid. These repairs are very expensive and not always even possible.

Let’s also not forget that improper transport of cryogenic liquids can result in very large fines. If you are not positive that your equipment is designed for liquid transport it is suggested that you ask a reliable source. There is nothing wrong with clarifying. And-You might just save someone from a serious injury.

4L DOT Cryogenic Liquid Cylinder Excessive Venting

The very best training sessions are those that get really conversational. Discussing case studies and reviewing alternative strategies are the root of “I learn as I teach.” One question asked this week was, “Do clients know to turn on their pressure builder isolation valves as soon as they receive their liquid cylinders?” The conclusion was that all too many users don’t know not to turn on the pressure builders on receipt.

A somewhat difficult issue applies when a system is set up with a primary and secondary bank of liquid cylinders tied into an automatic switch over control system. When the online bank of liquid oxygen, nitrogen or argon liquid cylinders runs low the system automatically switches over to the other bank. Since this could happen at almost any time the pressure builder(PB) valves have to remain open on the reserve bank.

If, though, it is known that the reserve bank will not go on line for several days then it is advisable to not turn on the PB valves right away. This is especially true if you have a Friday delivery to a facility that does not operate over the weekend. Just waiting until Monday to turn on the PB valve can add many days to the life of the liquid cylinders and greatly reduce product wasted to venting.

Cryogenic Liquid Cylinder Operation- Part 3- Pressure Building System

The April 16th article http://cryonews.blogspot.com/2009/04/cryogenic-liquid-cylinder-operation_16.html discussed why it is necessary to have a gas use coil that pulls liquid from the bottom of a 4L DOT Cryogenic Liquid Cylinder and vaporize it for gas use supply.

And- It was noted that a pressure building system is needed to help maintain pressure within a specified operating range. So, how does the pressure building system work?

Liquid cylinders equipped with gas use coils also have another set of coils brazed to the inside skin of the outer jacket. Just like the gas use coils- the pressure building coils pull liquid from the bottom of the liquid cylinder and vaporize it. Vaporization happens by exposing the liquid to temperatures above its boiling point.

Unlike the Gas Use system, the Pressure Building system returns vaporized gas back to the head space of the liquid cylinders. Crowding gas molecules into this head space raises the pressure of the liquid cylinder. The pressure building regulator controls the flow of liquid into the coils and stops the flow of gas back into the head space.

It is important to note, though, that this does not stop pressure from building. Once pressure is raised on a liquid cylinder and warmer air is introduced into the top of it normal evaporation of liquid nitrogen, argon or oxygen will increase. Be sure that the valves feeding pressure building regulators are closed if the vessel is not going to be used over night or over a several day period. Venting of pressure and release of hotter air can also help minimize product lost due to normal evaporation.

Cryogenic Liquid Cylinder Operation- Part 2B- Gas Withdrawal

The last two posts covered 4L DOT Liquid Cylinder Liquid Withdrawal and Vent operation. Summarizing- When the liquid valve is opened, liquid is drawn up from the bottom of the vessel through a dip tube. When the vent valve is opened gas is the top head space of the vessel is released. And- it was determined that the gas use valve cannot withdraw gas in the same manner as the vent or pressure would rapidly drop below needed levels.

“If gas doesn’t just pull right off the top, then where does it come from?”

Would you believe “It depends?”

And, in this case, what does it depend on?

It depends on the pressure of the contents compared to the setting for the pressure builder and economizer regulators which will be discussed next time. For now- the economizer setting will typically be about 15psi higher than the pressure builder setting. So, if your pressure builder regulator is set at 125 psi the economizer regulator actuate at about 140 psi.

When the contents pressure is below the economizer set point then the gas coming out of the cryogenic liquid cylinder actually originates from the bottom of the liquid cylinder. It comes out of the inner vessel through a small copper tube that is brazed to and circles around the inside of the outer vessel. Confusing? Not too. The key here is that, up to the point of needing gas, the purpose of the cryogenic liquid cylinder has been to protect the liquid oxygen, nitrogen or argon from outside energy (heat) in order to keep it in liquid form.

When gas is needed, all we have to do is expose the liquid to energy (via direct exposure to the outside wall of the vessel) to bring it above its boiling point. Now we have gas. By withdrawing liquid from the bottom and converting it to gas the head pressure of the liquid cylinder contents can be maintained far more easily. This provides more consistent output and allows the supported process to run normally.

The other aids to maintaining pressure within a usable range are the pressure building (PB) regulator, PB coil and economizer regulator. Stay tuned for more…….

Cryogenic Liquid Cylinder Operation- Part 2A- Gas Withdrawal

Open the Gas Use valve on a filled cryogenic liquid cylinder and gas will come out. Interestingly enough, the same thing happens if you open the Vent valve. So……. Does the gas coming out of each valve come from the same place inside the vessel?

If you answered “yes” or “no” you are sometimes right. As they say, though, even a broken clock has the right time twice each day. It is more accurate to say “It depends.” To understand the “why” of this, it is helpful to first look at the Vent connection.

We previously affirmed that liquid withdrawn from a 4L-DOT liquid cylinder comes from the bottom of the vessel. This is easy since the liquid is heavier. Gas that is formed by the normal evaporation of liquid nitrogen, argon or oxygen collects in the top of the liquid cylinder inner vessel “head space”. As more and more molecules crowd into the head space the inner vessel contents pressure increases. This pressure is useful to push liquid back out through the dip tube when the liquid valve is opened.

When the Vent valve is opened, free gas molecules are allowed to escape and the pressure goes down. If the Vent valve and Gas Use valves were both connected to the head space only then there would be no reason for both. There would also be a big operational problem.

Let’s consider a case where Mike the Scrapper is using oxygen from a cryogenic liquid cylinder to feed a cutting torch or oxygen lance. If he were using a simple LS (Liquid Service Only) vessel then his work cycle would look very much like the profile of a wedge or the topography of the White Cliffs of Dover. He’d have a long wait while pressure built in the liquid cylinder. Then, once the pressure was high enough he’d fire up his torch and start pulling off gas. The pressure would drop precipitously until it got too low and the torch would go out. Mike would then have to wait a long time again for pressure to build and then fire up for a little while, lose pressure and go out. This would be unlikely to occur more than a couple of times before Mike would give up on the liquid cylinder and go back to high pressure cylinders that would give him a constant supply of gas until empty.

If gas doesn’t just pull right off the top, then where does it come from?

Cryogenic Liquid Cylinder Operation- Part 1- Liquid Withdrawal

Is pressure good or bad in terms of cryogenic liquid cylinders?

A) Good
B) Bad
C) It Depends? (The Millennium Answer)

Right- It depends. Pressure is necessary for liquid and gas withdrawal from a liquid cylinder. Too much pressure, though, can cause excessive venting or even severe damage if safety devices are absent or malfunction.

As a first simple step it is important to understand that when liquid is filled into a cryogenic liquid cylinder it goes in through a dip tube that goes down to near the bottom of the liquid cylinder. When liquid is withdrawn it comes back up from the bottom of the tank through the same dip tube. Since the valves and connections for a liquid cylinder are at the top it is necessary to have some head pressure on the liquid in order to push liquid oxygen, nitrogen or argon back up and out the liquid valve.

The simplest liquid cylinders then contain only two valves (Liquid and Vent) and are often referred to as “LS” vessels. They are used for liquid service only and typically fitted with 22psi reliefs to avoid spraying liquid out with too much force when withdrawn. They really on normal product evaporation to create head pressure for liquid withdrawal.

This is all pretty simple, right?. Next we’ll discuss “VGLs” and Gas Withdrawal.

High Pressure Options for Oxygen, Nitrogen & Argon

How can efficiency be optimized in cases where high pressure is needed for purging, testing or other high pressure applications? First, it is important to understand the application and the factors that play into system design. Once the application is better understood then consideration needs to be made for the specific installation and location. Sometimes, the “best” method is not the most practical or cost effective. And supply of materials or availability of services can be a restraint.

One of the major justifications for liquid cylinders or cryogenic bulk tanks is the ability to get molecules to a user in a lighter and more compact package. Depending on the gas used, one liquid cylinder might be a direct replacement for a 12- or 16- pack of high pressure gas cylinders. This one 4L DOT cryogenic liquid cylinder full takes up only a 21” square footprint and weighs well under 1000lbs versus the high pressure pack with a 4x4 or so footprint weighing 3000 pounds plus. And- a 500 gallon GOrilla portable cryogenic vessel could take the place of ten high pressure packs at only 8000 pounds or so full.

An application can be a real bear when the minimum pressure is high enough to require high pressure gas cylinders or tubes and the volume of gas used is fairly high. In many cases, this can result in the need for a dozen or more high pressure 12- or 16-packs on site with a like amount committed back at the plant for exchange. This becomes an even bigger issue when the volume of oxygen, nitrogen or argon molecules needed necessitates a high pressure tube pack or trailer. If tubes are exhausted it becomes necessary to:

a) have a complete replacement pack;
b) have a spare for exchange stock or
c) have the ability to “bump” the tubes in the field.

More exploration of these options and consequences soon…….

Lifting Cryogenic Liquid Cylinders?

Try getting a consensus on issues related to lifting liquid cylinders up into overhead work areas. Good luck. As few manufacturers of cryogenic liquid cylinders as there are, the only consistent answer I could get is “Do Not Lift by the Handling Ring.” And- this is extremely important. There are many cases where lifting devices were attached to handling rings and the cylinders lifted up with bad consequences. Clearly, everyone I talked with agreed that handling rings are not a lifting point.

Beyond that, I was curious on the various manufacturers’ position related to using the eyes in the handling ring support posts for lifting filled vessels and made calls to all. Responses varied and the reasons became obvious pretty quickly. Some of the original manufacturers either no longer exist at all or have been acquired by others. This is important as there are still liquid cylinders that are in use since the 1970s and the differences is designs for liquid oxygen, nitrogen, argon and carbon dioxide cylinders are subtle, but meaningful. Almost all include holes in the handling ring support eyes that are used as catch points for cylinder handling carts. These carts have a hook which slips into the hole and grabs it so the liquid cylinder can be tilted back in the cart and rolled. This is a widely agreed method for moving liquid cylinders as long at the user has a cart designed for the purpose and is using it in the proper method.

The real question comes up when it is necessary to get a liquid cylinder up to a 5th floor work area at a site under construction or demolition. Without going into the variety of responses related to engineering of supports for lifting and potentially proper devices I’ll take a different tack.

- Do you know where that liquid cylinder was last month, last year, last decade?
- Do you have a document in front of you clearly stating that the lifting support stanchion holes for the exact model of vessel you have are intended for lifting full liquid cylinders overhead including instructions on the proper method and device?
- Do you have an inspection report certifying the current condition of the welds and metal?
- If not- Why risk it?

The picture attached shows a common condition of cryogenic liquid cylinders received by West Cryogenics for repair. Note the bent supports and associated stress to the head. Corrosion of outer vessels is also frequent. All of these change the game from original design and might not ever be discernable after a good rehab job. The safer approach for lifting would be to use an approved lifting cradle, freight elevator or other device rather than a direct connection to the vessel. Personally, I’d rather have the excitement of seeing my wife and kids and watching “House” or “Top Chef” than dealing with the aftermath of a liquid cylinder that tore loose from its lifting hook 40 or 50 feet in the air.

Vacuum Rupture Disk D- CSI Outer Leak

Another client met me at the door saying, “Your timing is perfect. Come back to the plant and see what you can tell us about this freshly rehabbed vessel that we are having some trouble filling.” The problem was apparent from about ten feet away. We walked on up to the vessel and found a neat hole (about welding wire diameter) that went through the plastic rupture disk cover, the “Do Not Remove” warning and apparently through the rupture disk. The plastic cover and label were removed to reveal the expected “sucked in” rupture disk. This was obvious tampering and one of the few times I’ve seen it done through the rupture disk cover.

Vacuum rupture disks plastic covers are put on cryogenic liquid cylinders both to prevent tampering and to protect the very thin disk material from welding and cutting sparks and corrosion. A supplier who is able to consistently assure that all liquids go out with rupture disk covers in place is both protecting their assets and providing a ready visual indicator for drivers to help with spotting potential problems.

Many of the liquid oxygen, argon, and nitrogen bottles that come in with blown rupture disks are clearly tampered with. Spotting problems at the user site and documenting them helps with the possibility for recovering the cost of repairs for damages.

A lot of people believe that “if you take care of the nickels the dollars will follow.” Here is a case in point.

Blown Rupture Disk C- CSI Inner Leak

Delivery Company Y makes a delivery to my shop. Two weeks later I call them and say I just got to this box, it is damaged and I want to place a claim. Unable to stand the sound of their laughter I hang up. Much is the same when a gas supplier tries to call their client two weeks after picking up liquid cylinders to say that some of them are damaged and they are going to bill the customer. The difference is that the reaction from the client can be a little rougher than laughter.

Having alert drivers who pay attention to what they are loading at pickups, note damage found and get customer signatures is priceless. Take for instance a cryogenic liquid cylinder that has a bent handling ring, piping and a dent on the head. Looking a bit further the driver finds that the vacuum rupture disk is blown out. This is pretty simple. The liquid cylinder has been dropped and there is now an inner leak at the neck or some other point. The contents (oxygen, nitrogen, argon or CO2) has escaped into the annulus, built pressure and blown the rupture disk.

Now the cryogenic liquid distributor is confronted with either a costly repair $750 to $1000 or more or replacement of the liquid cylinder $2000 to $3000 or more. In the case of a larger “micro-bulk” vessel that is set down too hard and snapped a neck connection the replacement cost can be well over $10,000 to $20,000. And- it is really hard to tell if that happened at the customer’s site or the fill plant without documentation at pick up.

Note that all inner leaks are not the result of abuse. Some do occur due to manufacturing or design issues, but the chance of recovering or even sharing costs with users are greatly diminished without documentation…… and reasonably so.

Vacuum Rupture Disk- Blown B

A client called upset that they’d just received 20 liquid cylinders back from rehab and now had 18 in the yard “bad.” They wanted immediate attention and got it. Two things were obvious on arrival. The first was that there were no DOT-4L repair “K” tags on the vessels indicating right away that we’d never seen the vessels in question. Number two, and most upsetting to the client, was the very apparent indication that someone had intentionally punctured the rupture disk on 18 of the 20 liquid cylinders. This was obvious as the protective disk covers were missing and the disks were blown “in” instead of “out.”

The purpose of vacuum rupture disks for cryogenic tanks and liquid cylinders is to prevent rupturing of the outer vessel which has no pressure rating. Vacuum rupture disks are very thin, concave and surrounded by knife edges which are lined up just over the surface. A very low pressure build up in the annular space of an oxygen, nitrogen, argon or carbon dioxide cryogenic tank will cause the disk to protrude against the cutting edges and rupture allowing free flow of the gas to atmosphere. So- any CSI investigator who sees the disk blown out can readily tell that a vessel with a disk blown “out” probably has some type of inner leak.

A disk that is blown “in” indicates a leak occurred in the disk and the vacuum in the annulus sucked atmosphere from outside pulling the disk in. There are slip-on plastic protective covers installed over most disks to prevent damage that would cause a leak. Many manufacturers and service companies also install a warning between the cover and disk noting that removal or tampering will void any warranty of the vessel. This cover helps protect the disk from welding or cutting sparks and corrosion that could cause a vacuum space leak in the cryogenic tank.

When there is a good vacuum on a tank then rupturing the disk will cause a great whoosh of flow into the annulus. It is an all too common occurrence for vandals to remove the covers and puncture the disks. Whether their intent is malicious or just for entertainment the result is the same. The liquid cylinder now has no vacuum and will have to be sent in for a rather expensive repair.

Next, we’ll talk about responsibility and how cryogenic liquid suppliers can save hundreds of dollars by training their drivers to be alert to damage and consistent in documenting it on site.

Used Equipment Scarcity

Purchasing used or reconditioned equipment is one way of helping cash flow for startups and boosting the profits of established operations. Like any tactic, it is great if it works. During the past several years, though, it has gotten harder to find good used cryogenic tanks at any price. Here are just a few of the reasons:

- Rising steel prices and other costs have driven new equipment prices up considerably. This makes it easier for companies to justify rehabbing equipment and continuing to use it. Even if owners have no immediate needs they find it hard to sell off equipment when the cost of repurchasing a similar tank later is so high.

-Industry “Majors” regularly fed used equipment into the market until they realized that the equipment they were selling off was costing them business. Simply put- smaller independents were buying used cryogenic tanks and coming right back to take away clients by offering lower rental rates on cheaply purchased equipment. Many large companies now take the position that the opportunity cost of selling used tanks that end up in the hands of competitors far outweighs the sale price.

-Strong demand has made it easier to place liquid oxygen, nitrogen or argon equipment pulled from one site with another client in short order. In fact, suppliers have typically found that equipment moved to a new client generates higher rentals than at the old clients so upgrades are encouraged.

-Risk calculations also come into play for sellers who have to weigh short term savings against long-term exposure.

There are few clues on what will occur during 2009 related to used cryogenic equipment markets. For now there is nothing that indicates either an increase in availability or lowering of prices.

Cryogenic News Introduction

Thank you for sharing a moment or more of your time to check out this blog. It is my wish that you will find some of the information shared to be helpful, interesting, enlightening or even occasionally inspiring.

Cryonews is focused on items of interest to cryogenic industry suppliers, users, and students taking into account the wide diversity of people and applications in the field. Liquid Oxygen, Argon, and Nitrogen have an incredible number of uses in areas from Medical Oxygen in Hospitals, Research and Homecare to Manufacturing, Construction, Welding Jobs, Demolition, Food and Beverage Production, Harvesting, Special Effects and more. In turn, new posts will intentionally traverse a pretty wide open course going wherever the light shines that moment. And there will be frequent posts with no seeming relevance delivered guilt-free.

This blog is intended as a source for industry news, tips, and insights. Questions, ideas, and links that might be considered worthy of note will be valuable and appreciated. Inevitably, we’ll find that others are wondering or interested in the same things. I'll endeavour to provide responses that are accurate and avoid “the sin of being booooring.”