In industrial settings when gasses are stored under pressure in liquefied form, they are stored in tanks, cylinders, or dewars. As the gas is needed for use, the liquid is boiled off and released as gas through a valve that allows it to be channeled to a given area. The remaining contents stay in the container as liquid until the process is repeated.
Measuring Flow Rate to Determine Weight Change
In order to calculate the correct refill and replacement within the tank, one needs to know the amount of liquid gas left inside. This is accomplished by measuring the flow rate via the change of weight that occurs over a specific amount of time. This weight then determines when the tank is running out of gas.
Measuring this rate shouldn’t be difficult with any modern piece of valve equipment. You simply need to watch the dial or another readout to ensure that everything is within acceptable tolerances. Particularly sophisticated pieces of equipment have somewhat automated this process by leveraging digital-based technologies to provide extremely accurate readings.
Once you have the flow rate sorted out, you’ll be in a better position to get over to the scales and get an exact reading.
Cylinder Scales and Internet Connectivity
Cylinder scales are designed to accommodate a wide range of liquefied gases and relay weight information to a central area for monitoring. One way this happens is through Internet connection that flawlessly sends data for immediate and accurate readings.
Naturally, this makes the data collection process go much more smoothly. Your crews will be able to see everything in real-time as they monitor the Internet data feed from literally any kind of device that supports a modern browser. If you plan on carrying a mobile device around with you, then this should work.
An old PC reused as a data collection workstation will work just as well. The possibilities are endless since this technique leverages IT equipment that you might very well already have access to.
Putting Load Cells Into Play
Most ordinary electronic scales in use in the market can handle up to 300 pounds of weight. Larger tanks require larger platforms, most specifically those that can handle up to 3,000 or 5,000 pounds at a time. to get an accurate reading on these large weights, load cells are put into play. These are electromechanical devices created to convert weight into the electrical signal. To be even more exact, a load cell is a transducer that can convert force into a measurable electrical output to determine the refilling procedure.
As you might imagine, Arlyn Scales is always sure to only use the most accurate cells for the job.
Using One Load Cell
When only one load cell is used it normally relies on mechanical bearings to position the weight on the scale so that a proper reading can be made. But these bearings are prone to wear and corrosion, which compromises their accuracy over time. The use of one load cell is generally for lighter weight as well as for keeping costs low, as they are less expensive to produce.
That being said, you’re making a sacrifice in terms of quality versus cost when you elect to use a single load cell. Your scale will start to suffer and eventually have to be extensively re-calibrated or replaced. Ironically, this can drive the price up much more than had you used a more sophisticated scale, to begin with.
Using Two Load Cells
In order to keep a load in place, rollers and edges are often required. This position, however, can be difficult to maintain if the right amount of load cells are not used. Two load cells can help create more balance, but still, do not provide the ultimate accuracy that is ideal for weighing protocols. While they might be better than weighing devices that use a single load cell, they still represent something of a compromise.
Fortunately, there are better technologies available so you don’t have to feel like you’re constrained by whatever equipment you’ve been using thus far.
Strain Gage Load Cells
The most common type of weighing system used when it comes to cylinder scales is through the use of strain gage load cells, where the resolution amounts to one part in 5,000. The majority of this type of load cell is made of aluminum, which is inexpensive and easier to mold into whatever shape necessary. High-end scales employing strain gage load cells use plated steel. At Arlyn Scales, we only use stainless steel, which is durable, rugged, easy to clean, and designed for longevity.
Stainless steel comes in various grades, which you’re probably familiar with from examining any of a variety of tools that come made from this ubiquitous material. Arlyn’s engineers insist on only using the best type of stainless steel for our particular use cases.
Force Restoration Systems
A secondary technology for weighing cylinder tanks is called either Force restoration or Force motor. Here, the principle of the electromagnetic force opposing weight on a scale platform is used. In this scenario, there is a higher resolution and accuracy than found in the strain gage load cells, but there is also some temperature instability and drift. Force restoration scales are more difficult to use in scales designed to handle fifty pounds or more and are often damaged due to shock loading and overload. These weighing systems are additionally more expensive to manufacture than the strain gage model.
Should you have one that gets damaged it can also be difficult to find someone willing or able to repair it. They often use complex proprietary parts that few people would otherwise have access to, which can make this a difficult proposition. Even if you can find the right replacement parts they can still be expensive to repair.
Fortunately, all scales manufactured by Arlyn come with a specific guarantee and they’re backed by a large collection of aftermarket components that you could easily install on whichever model you’d like.
Legacy scale support is a major part of our mission since we want to be sure that small business owners always have all of the tools they need to complete difficult tasks.
Aftermarket Equipment for Tank Filling Scales
Having extremely accurate loading systems is only part of the equation. Digital indicators are another excellent way to ensure that you have the best measurement possible. Some of these indicators include the special circuits needed to achieve networking capabilities. If you’re currently working with equipment that lacks Internet connectivity, for instance, then you could easily install one of these aftermarket units onto any compatible scale from Arlyn to add it and start enjoying some additional functionality.
Touchscreen capabilities are also quickly becoming popular with many users. While discrete buttons are always going to be preferred in some industries, things are changing and people are looking for easier ways to take measurements when they have full hands. This has a tendency to happen more often than not in any productive operation that has to concern itself with filling tanks and cylinders, which makes it a particularly attractive option even to those who might not otherwise have considered it previously.
The Surface Acoustic Wave
Arlyn Scales has developed a third technology called Surface Acoustic Wave , or SAW. Using a similar technology that is found in the fabrication of semi-conductor integrated circuits, SAW produces a highly precise digital output with ideal resolution and accuracy unparalleled in the weighing industry. With this revolutionary technology, there is greater temperature stability and an extremely high tolerance to shock and overload due to the integration of a very rigid load cell block. Able to handle capacities up to 5000 pounds, this system is twenty times as accurate as the strain gage system, at less than one third of the cost of equivalent force restoration scales.
Even if you’re not quite as familiar with this innovative technology as you might be with some of the more common systems in play, SAW scales have a great deal to offer you. This is especially true if you’re loading tanks under laboratory conditions that require extremely exacting measures.
Keep in mind that these scales are by no means small necessarily. You can opt for SAW scales that are capable of handling very large objects without sacrificing anything in the way of accuracy. While this might be a bit paradoxical to some, it works out quite well.
Providing Durability and Longevity
When it comes to the advancement of providing accurate measurements for any type of weight system, Arlyn Scales is superior to all of its competitors. Instead of relying on two load cells, we put one load cell in each corner of a scale platform, which means there are four load cells on every unit. This means that the entire system is designed to be completely electronic, with no pivots or bearings needed for extra stability or positioning. As a result, there are no moving parts that can be damaged. Unlike many weighing systems that are made from aluminum or nickel-plated steel, which can deteriorate in corrosive environments, ours are made of stainless steel. This means resistance to fumes, damaging liquids, moisture, and water vapor. Using a special alloy of heat-treated stainless, our machines boast a durability and longevity not found anywhere else in the industrial scale marketplace.
No Compromise to Accuracy
Using four load cells also allows gas cylinders and tanks to be placed anywhere on a platform, with no compromise to the accuracy of a weight reading. These rugged cells provide everything necessary for the most precise transmission of information when it comes to calculation and refill.
Ideal Scale Platforms
Another essential area to look at is the scale platform itself. Many of Arlyn Scales competitors manufacture them from steel that they coat with specific kinds of paint to protect them from corrosion. There are also a number of plastic versions that are employed for weighing purposes. In both cases, any exposed metal components will corrode, thus interfering with the electronic signals that are essential to the weighing and transmission process. Our scales are shielded from both electromagnetic and radio frequency interference due to our unequivocal use of stainless steel.
Whether you need weighing systems that employ load cells for commercial, laboratory, or medical applications, Arlyn Scales has the most evolved and state-of-the-art systems in the marketplace today. For more information on what we can offer or fabricate for you, please contact us via our online form or by calling 800.645.4301.