The Science Behind SAW Technology


The Science Behind SAW TechnologyIn the past, companies that were looking for accurate, precise measurements were left with few options when it came to industrial scales. Finding a scale that offered high-resolution readings, without costing a large fortune seemed like a pipe dream, until Arlyn Scales unveiled their patented Surface Acoustic Wave (SAW) technology.

Arlyn Scales has been a leader in the design and manufacturing of high quality industrial scales for more than 30 years. In this time, we’ve worked hard to develop an array of new discoveries that make the daily lives of our customers easier. Our Surface Acoustic Wave scales are our most advanced innovation yet.

SAW Scales Can’t Be Matched

Our SAW scales feature 10-20 times superior accuracy compared to strain gage scales, and provide similar accuracy to that of magnetic force restoration scales, yet cost roughly one third the price.  To better understand the power of our SAW technology, it’s important to understand the issues plaguing some of the most commonly available scales on the market today.

Problems with Strain Gage Scales

Strain gage scales are still the most popular type of scale used today due to their versatility in a wide variety of industrial applications, as well as their relatively low cost.  These scales utilize strain gage load cells, that when manufactured out of high-end materials like stainless steel, can be durable, rugged and reliable.

It’s important to understand that strain gage scales are not sufficient for any applications that may require highly accurate and high-resolution weight readings. Industries where hundredths of a pound could severely affect the viability of a product should not use strain gage scales.  Examples of applications that need more precise readings than can be provided from strain gage scales include chemical, pharmaceutical, paint mixing and semiconductor applications.

Scales that use strain gage technology typically are accurate to around 0.1%.  While this small amount of material may not matter in certain applications, it can be incredibly important in circumstances where a small weighing error can create catastrophic problems.

Strain gage scales will also lose resolution (number of digits the scale can measure) as their maximum capacity increases.

Do MFR Scales Solve the Problem?

In the past, industries requiring high resolution, accurate weight readings such as paint mixers, laboratories, semiconductor manufacturers and chemical facilities, often relied on magnetic force restoration scales, despite their shortcomings.

Magnetic force restoration scales do not use load cells, and instead rely on an electromagnet to counterbalance the weight of an item on a scale’s platform. One of the main problems with these scales, however, is that their maximum capacity is only between 25-50 pounds, at best.

MFR scales are also extremely expensive, hard to work on, and can be difficult to operate. In addition, magnetic force restoration scales can be vulnerable to accuracy issues as well as changes in temperature, currents and vibrations. Because of these shortcomings, MFR scales are not well suited for environments where these conditions are present.

While MFR scales do offer high-resolution measurements at low capacities, they’re still not practical for most industrial applications.

Arlyn SAW Scales – Precision Measurements at High Capacities in Industrial Environments

Thanks to Arlyn Scales’ patented SAW technology, industrial customers no longer have to worry about any of the drawbacks of either strain gage or MFR scales.  Our SAW scales offer highly precise measurements, rivaling those of MFR scales, at prices that cost roughly the same as a high-end strain gage scale.

At Arlyn Scales, we’ve taken the knowledge we’ve gained over the past 30 years in the industry and improved upon it by offering our internationally patented SAW technology that allow for high resolution scales that can still be both highly accurate and precise.  On top of the accurate measurements and high capacity, our SAW scales are also extremely rugged, which is key in most industrial applications.

Mechanics Behind the Design of our SAW Scales

Instead of having to use strain gage load cells, we’re able to use much thicker load cells because the amount of bending required of our SAW technology is roughly one tenth of the amount needed with a standard strain gage load cell. Rather than measuring strain or stress, as is the case with strain gage scales, SAW scales measure displacement. This makes them much more reliable, and better suited for highly taxing industrial environments.

Our thicker load cells are a much better choice compared to the thin metals often used in strain gage load cell design, which are much more susceptible to overloading (placing a load on scale platform that far outweighs its capacity) or shock loading (when a load is dropped onto a scale’s platform from a height).

Reliable and Rugged

Our SAW transducers are much more accurate than competing load cell designs, allowing our scales to display fully digital output readings with high resolution. In addition, because readings are taken digitally, they’re more accurate and have increased sensitivity to small changes in weight. The spring element used in SAW load cells has two surface acoustic wave transducers that are attached; one serves as the transmitter, while conversely, the other acts as a receiver.

The transmitter creates a bulk wave and then passes the signal to the receiver, where it is amplified and immediately sent back to the transmitter, where the process is repeated. When the spring element bends, the wave frequency that is being sent between the transmitter and receiver changes. By digitally measuring this frequency, our SAW scales are then able to determine the weight on the scale platform.

Superior Capacity and Readability

Readability is a common measurement used by scale manufacturers to help measure performance. This measurement can be calculated by dividing a scale’s maximum capacity by the scale’s resolution.

Most strain gage scales will advertise a readability of roughly 1:5,000, compared to SAW scales that feature a readability of 1:100,000. Our SAW scales feature a readability that is roughly 20 times better and accuracy that is 10 times greater than your standard strain gage scale.

In addition, our SAW scales have a capacity of 1000 pounds, or more. At 1000 pounds, our SAW scales offer a resolution of 0.01 pounds, compared to 0.2 pounds for a strain gage scale with the same capacity.

Still Have Questions About the Science Behind Our SAW Scales?

If you’re looking for more information about what makes our SAW scales superior to both strain gage scales as well as MFR scales, feel free to reach out to our customer support team today at 800-645-4301 or through our online contact form.