exploding plastic storage tanks

[Jon Stratis]

This past week at the Lake Superior regional we had one of the plastic air tanks from Clippard explode on the field, sending pieces all the way up into the stands (at LSR the stands start about 10 ft above the field, with plenty of space between them and the field), and I heard there was a tank that blew in week 1 as well.

At LSR, we believe the failure was caused by damage to the tank, not a manufacturing defect (like a void in the plastic wall). The team used hose clamps to attach the tank to their robot - the screws from the clamps bit into the sides of the tank, and when reassembled the tank was slightly deformed from being squeezed by the clamps. As far as we can tell, the initial fracture point was right under the clamp, near the screw. Further, the tanks were mounted in a very exposed position, and took some hits from other robots.

I want to strongly caution teams to mount these tanks properly (with the provided plastic clips or through some other means that holds them securely without applying undue pressure on the sides of the tanks) and to protect them inside the frame perimeter. The tanks were designed for a much gentler use than we're putting them through (mounting to a static mechanism that doesn't take impacts or damage, and doesn't need firm mounting to hold the tanks in place), and rough handling will eventually lead to failure!