December 1, 2006
equipment & applications | Cubing & Weighing

The weight of measures

the weight of measures

Accurate calculation of "dimensional weight" is carrying greater, well, weight in parcel shipping rates. That's leading to greater interest in tools that measure up to the demands of high-speed cubing and weighing.

By George Weimer

How much does an inch weigh? That might sound like the kind of nonsensical question Lewis Carroll might pose, but in the world of small parcel shipping, the concept of "dimensional weight" is important—and becoming more so. In essence, it's the system developed by parcel carriers as a way to ensure that lightweight but bulky items pay for the space they take up in trucks and planes. To determine the correct rate for a parcel, the shipper must determine both the package's weight and its dimensions, and then check the carrier's rate schedule to figure out which to use as the basis for the charge.

The major air and air-express carriers have all invested millions of dollars to install complex, highspeed weighing and dimensioning systems in their hubs. They try to dimension and weigh every package to determine what the correct rate should be. If it's different from the customer's rating, the difference (and sometimes a penalty fee) shows up as a back charge on the customer's bill.

While dimensional weight charges have applied to air shippers for years, they're about to be introduced into the ground service business. UPS announced just a few weeks ago that, effective Jan. 1, 2007, "oversize" rates will be replaced by "a simpler rate calculation based on dimensional weight." As currently written, this new policy applies only to packages over three cubic feet (5,184 cubic inches). (Smaller-volume packages will continue to be billed by actual weight alone.) Under the new policy, says UPS, "[b]illable weight will be based on actual package weight or the dimensional weight, whichever is greater."

"Dimensional weight" or "DIM weight" as it is commonly called, is determined by dividing the volume of a package in cubic inches by a constant, typically 194 for domestic or 166 for international shipments. The greater of either the DIM weight or the scale weight must be used for rating the package. For large, light boxes, the DIM weight rate will almost always be higher.

Size matters?
That might not sound like a big change, but the implications for shippers are huge. As the volume of packages subject to DIM weight rates increases, so will shippers' need to obtain precise information on the weights and dimensions of packages leaving their DCs with parcel and express carriers.

If we're talking a package here or a package there, gathering the weight and cube information might not be a big deal. If you're talking thousands of boxes, though, it quickly becomes a complex—and costly—business challenge. All too often, warehouse and shipping workers make a rough stab at the package's dimensions or, more commonly, ignore the size altogether because they're in a hurry to get orders to the dock, and rely solely on weight taken from a scale.

Do that these days, however, and your bill is likely to include back charges, says Phil Metzler, strategic product group leader, shipping and mail business for Mettler-Toledo. Thus, all manner of new devices to measure and weigh with ever-increasing accuracy and speed are showing up in warehouses and logistics hubs throughout the supply chain.

Mettler-Toledo, for example, offers cubing systems that use a variety of technologies, including lasers, photo diodes and both static and dynamic scales. "The goal is to provide systems that are modular in nature, that allow easy integration into existing material handling systems, and that easily aggregate data for communication to a host computer system," says Mettler-Toledo's strategic accounts manager, Bob Pacotti.

No shortage of choices
One of the pioneers in this technology is Quantronix of Farmington, Utah, which markets the Cubiscan series of dimensioning machines. Cubiscan systems come in a variety of configurations—from ceiling-mounted devices that allow omni-directional access to the measuring area to portable systems that can easily be moved around the plant or warehouse. "Large static cubing systems are new in the past few years," reports Randy Neilson, director of sales and marketing for Quantronix.

Each type of model has its strengths. Small static systems, for example, are good for measuring small and irregular shaped items, but they usually aren't the right fit for large crated merchandise or palletized goods. Larger systems are suitable for those larger items but generally are incapable of handling smaller items, Neilson explains. He suggests customers take a look at using two or more systems to cover all of their needs.

Cubing or dimensioning systems use low-powered laser technology (similar to bar-code scanning) or infrared light or ultrasound to measure packages. The technologies vary, but the idea is the same in all cases—accurate, defendable measurements of volume.

And that's a concern whether you're a shipper or a carrier. "There's only so much space on a truck," says Gordon Cooper, vice president-marketing for ExpressCube, a division of Mississauga, Ontario-based Global Sensors. ExpressCube will soon enter the U.S. market with its dimensioning system, which uses photo diodes. Developed for Cardinal Couriers, a regional carrier in eastern Canada, the technology will be demonstrated at the ProMat show next month in Chicago.

What's ahead?
Suppliers of automatic scales and cubing systems say that the systems pay for themselves in months by eliminating the inaccuracies associated with hand weighing and measuring. "You can save maybe 10 percent on your backcharging bills by using automatic or semi-automatic weighing and cubing technology," says Joe Flaviani of Schneider Electric, which markets weighing devices and offers consulting expertise on cubing, weighing and other material handling applications. "The cost savings alone usually more than justify the investment in these new systems."

"One of our systems saved the user $155,000 per year in back charges. That's on a $15,000 investment in this kind of technology," adds Mettler-Toledo's Metzler.

As for what's ahead, it seems that for scales—particularly the huge scales used to weigh whole semis and train cars— the trend will be toward automation. "More and more we're building truck weighing systems that are unattended," says Larry Behrens, industrial products manager for Fairmont, Minn.-based Avery Weigh-Tronix. "We're also doing more and more with RFID," he adds.

As for cubing systems, Cooper foresees big "changes in this field in terms of price reductions due to increased volumes, and ease of operation and setup." He's also optimistic that those advances will lead to increased sales. In the near term, he says, "[w]herever you find a scale in business, you'll find a cubing machine as well."

"Automated dimensioning will continue to migrate from the carriers back through the supply chain. Today you see increased focus on parcels and packages, but soon, you'll see more focus on palletized goods. They have the same size and weight issues as individual packages," predicts Mettler- Toledo's Metzler. "You'll also begin to see more use of dimensioning technologies at retail and point-of-sale (POS) counters, such as at a UPS store or FedEx Kinko's." Adds Pacotti, "You may not see fundamentally different technology, but rather ways to better package all the data ... in ever-more simplified ways. The IT manager always wants more simplicity."

Weighing and measuring used to be two of the simplest tasks in the DC. Over the past few years, they have become more and more high tech. Every sign suggests that the trend will continue as shippers and carriers keep trying to balance—and dimension—the fees and costs of moving packages through the supply chain.

About the Author

George Weimer
Editor at Large
George Weimer has been covering business and industry for almost four decades, beginning with Penton Publishing's Steel Magazine in 1968 where his first "beat" was the material handling industry. He remained with Steel for two years and stayed for two more when it became Industry Week in 1970. He subsequently joined Iron Age, where he spent a dozen years as its regional and international machine tool editor. He then re-joined Penton Publishing as chief editor of Automation Magazine and in 1993 returned to Industry Week as executive editor. He has been a contributing editor for several publications, including Material Handling Management, where his columns and feature articles regularly generated lively discussion in the industry. He has won various awards from major journalism organizations. He has covered numerous trade shows here and abroad and has spoken to various industrial and trade groups on the current issues and events of the day as they impinge on business. He remains convinced that material handling technology and logistics are two of the major sources of productivity improvement today and in the future for all industries.

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