The million-pound hammer
Of all the devices that pulverize, crush, vibrate, flatten and stretch in the name of materials testing, one university machine separates the tools from the toys.
By its name alone, one can easily appreciate the gravity of a “Million-Pound Test Machine.” The device, housed at Engineering Hall, is a James Bond movie villain’s dream: It stands five stories tall with two towering side rails, a circular staircase and catwalk. Its giant hydraulic head moves suspensefully slow, crushing its target at one inch per minute.
  Top: College of Engineering operators, left, gather behind a shielded control panel to bring some weight to bear using the college’s unique load-testing device, a sort of slow-motion hammer that can bear down with a maximum million pounds of force. That’s enough to squash just about anything, say testers who have used it to crush items ranging from a 1964 Ford Fairlane to materials used to support stadiums and other structures. Bottom: A cast-iron manhole withstood 700,000 pounds of force before finally cracking under steadily increasing pressure applied by the relentless load-testing device. |
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Crunch time: Meet their demise So what’s it take to squash some common items? Here’s a sampling:
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The machine is one of only about a dozen like it in the world. And despite being nearly 60 years old, it remains a vital teaching and research device on campus, and a tool for major materials-safety jobs in private industry.
In recent years, the device has helped test materials going into major professional stadiums, nuclear power plants, mining equipment and highway projects.
“They don’t make machines like this anymore,” says Steven Cramer, a civil engineering professor and director of the Structures and Materials Testing Laboratory. “It’s our big hammer.”
Cramer says the laboratory has more than 50 devices that deliver and measure stress, defining the breaking points in materials such as steel, plastic, wood, concrete and asphalt. Materials testing ensures that products will withstand the wear and tear they’re designed for. “We can do practically any materials testing job in one of our labs,” says Cramer. “But with that machine here, we always have the fallback option of a bigger hammer.”
The machine got its start in Madison in 1962, when it was purchased from Northwestern University’s engineering school. According to John Dreger, electronics technician for the UW–Madison lab, Northwestern had declining use for the device and needed the space it inhabited.
Dreger found documents showing that Northwestern paid $300,000 for the machine back in 1942, when it was built and installed by the Baldwin-Lima-Hamilton Corp. UW–Madison got it for the bargain-basement price of $65,000.
About 15 years ago, Dreger upgraded the machine from old manual controls, which looked like captain’s wheels on a boat, to fully automated computer controls. Since then, it has enjoyed a resurgence of use among researchers and companies with specialized needs.
Last summer, for example, the hammer helped test the construction process for 130-foot concrete beams supporting the retractable dome roof at Miller Park, future home of the Milwaukee Brewers. Also in summer 1998, engineers for the Houston Astrodome tested a big flexible steel and plastic pivot for its retractable roof.
The machine has crushed concrete pipes for sewer systems, manhole covers for city streets and steel poles for interstate lights. Back in the 1960s, Ford sawed several cars in half and crushed their front-ends in the hammer, to gauge the “accordion effect” of their frame designs. The designs were a precursor to the impact-absorbing frames that are common today.
In addition to crushing, the device can also stretch products. They used downward tension of the machine to test crane hooks that lift fuel rods from nuclear power plants and foot-thick industrial chains for mining equipment.
It allows for some innovative research projects among faculty. Cramer ran a test to see if compressed wood could be used as a shock-absorbing packing material around hazardous waste containers. Another researcher tested the elastic nature of a new type of highway guardrail design. One year, researchers crushed a ripe pile of garbage to find out how much it can be compressed.
William Lang, a senior instrumentation specialist who along with Dreger manages the lab’s day-to-day operations, says instruction and research take priority over any industrial use of the machine. But outside contract revenue has been helpful for maintaining the lab.
As many as 500 engineering students work in the materials testing lab each year, either in undergraduate classes or graduate research. Lang says he gives the occasional curious students or parents a tour of the facility. But even those who never see the machine have probably felt it.
“Everybody knows when we’re testing something down here,” Lang says. “When the material breaks and everything relaxes, the whole building quakes.”
In an age of computer wizardry, where nearly every step of product development can be digitally simulated, there is still no substitute for reaching out and crushing something. “The hammer” removes any gray areas between the theory and the reality of material performance.
A quote on the laboratory bulletin board reinforces that message: “One test is worth a thousand expert opinions.”
Tags: research