While HGST, a division of Western Digital Corp., has already announced plans to release helium-filled hard disk drives with increased number of platters in 2013, its arch-rival Seagate Technology doubts that the so-called "sealed-drive" technology is the right one to boost capacities of hard drives as it creates new challenges and risks.
The density of helium is one-seventh that of air, which means dramatically less drag force acting on the spinning disk stack inside hard disk drives so that mechanical power into the motor is substantially reduced. The lower helium density also means that the fluid flow forces buffeting the disks and the arms, which position the heads over the data tracks, are substantially reduced allowing for disks to be placed closer together (i.e., seven disks in the same enclosure) and to place data tracks closer together (i.e., allowing continued scaling in data density). The lower shear forces and more efficient thermal conduction of helium also mean the drive will run cooler and will emit less acoustic noise. Recently HGST revealed plans to launch the industry's first helium-filled HDDs for datacenters, where increased per-drive capacities directly affect such measures as cost-per-terabyte, watt-per-TB, TB-per-system weight and TB-per-square foot.
The former Hitachi GST, which now belongs to WD, is not the only company on the planet, who researched helium filling for magnetic disc-based storage devices. Seagate Technology has also investigated helium-filled hard disk drives and even has 80 patents in the area. In fact, it claims that it started to consider the sealed drive technology earlier than its competitors.
"We have explored helium filled drives ('sealed drive' technology) as well as many other technologies for delivering higher capacities and lower TCO. Seagate has been working with helium from the earliest days, probably earlier than anyone in the industry. We have over 80 patents related to this technology today and will continue to explore its viability, its benefits as well as its potential costs and risks," said Jon Piazza, senior manager of corporate communications at Seagate, in a conversation with X-bit labs.
Seagate admits that Helium filling can solve a number of challenges, but it creates new ones and naturally generates new risks, which is why the company does not seem to have solid plans to use the sealed drive tech the foreseeable future. Seagate believes new methods of magnetic recording could be just more practical, which is hard to disagree with as they will benefit all hard drives from top-to-bottom of the product stack, whereby helium-filling is an expensive tech that is currently considered only for expensive datacenter-class solutions.
"Helium can solve some internal technical challenges, but it also creates new challenges, like how to prevent leaks and bring down manufacturing and materials costs. Fortunately, we have been able to advance our drive technology and capacities without resorting to filling our drives with helium. We are also working on alternative technologies such as heat-assisted magnetic recording (HAMR) and shingled magnetic recording (SMR) as potential ways to advance drive capacities in the future," explained Mr. Piazza.