September 13, 2012

Do Helium-Filled Hard Drives Sound Funny?

Michael Harper for — Your Universe Online

Western Digital´s newest subsidiary is faced with a problem: Though technology has been, and always will be, shrinking in size, how do hard drive makers get as much efficiency as they can from the space they´re given? Today, they´ve announced a new hard drive with a very interesting solution to this problem: Helium.

HGST, or Hitachi Global Storage Technologies, has said they expect to begin filling hard drives with the lighter-than-air gas as early as next year, making them the first hard drive manufacturer able to do so.

"It's our biggest technological innovation in the last eight years," said HGST´s vice president of product marketing, speaking to

"We've been filling hard drives with air forever."

With these new, helium-filled hard drives, HGST will be able to pack in more platters in the same amount of space, moving beyond current 5-platter 3- and 4-terabyte models.

But why helium? Hard drives spin very quickly to access and write data to these platters via an arm which rests very closely to their surface. Thanks to the laws of physics, when these hard drives spin, they create drag, which not only forces the hard drives to work harder, it also means hard drive makers like HGST have to leave extra room in the enclosures as a buffer to reduce turbulence and vibrations of the heads.

“At some point in the next two to three years, you can't push the capacity in air," said Collins.

"We will need to migrate to a new platform. We can go to a smaller form factor where there is no flutter. But that would double the cost per GB."

Though HGST (who was acquired by Western Digital just last year) is the first to create a commercially viable way to produce these helium hard drives, they certainly aren´t the first to have the idea. By using helium, these hard drives can spin with a significant reduction in drag, thereby eliminating the need for buffer zones and allowing hard drives to require less energy to spin the platters at full speed.

According to a white paper published by a California hard drive maker, Xyratex, the notion of pumping enclosures with helium was patented back in 1980.

The trick to this process is finding a way to keep the helium locked within the enclosure without it slowly seeping through the cracks.

“The breakthrough is in the product and process design, which seals the helium inside the HDD enclosure cost effectively in high-volume manufacturing," proclaimed Steve Campbell, HGST´s CTO in an interview with The Inquirer.

After years of work, the engineers at HGST have found a way to hermetically seal their enclosures, keeping the magic helium in and damaging air out. Currently, this process is being used on large-capacity, 3.5-inch drives with a 95 mm diameter, according to Collins.

"The bigger the disk, the more the flutter, and so helium helps," he said. "Performance drives use 65 mm disks, so there is less flutter. But that may be an issue in another three to five years."

Another issue HGST may face in the future is the limited supply of helium. The U.S. government stockpiled large quantities of the finite gas during the days of World Wars 1 and 2, then began to sell if off in mass quantities in 1966 to recoup their initial investment. Now, the price of helium does not accurately reflect the true value of the gas as many buy up helium for whatever application they choose.

By 2015, the cost of helium could rise by as much as 50% before the Earth´s supply is finally depleted.

Until then, HGST has said they´ll have the first models of these one-of-a-kind hard drives available sometime next year.