Gas Spring Adds Dampening to Self-Tilting Stillage Design

AEuropean manufacturer and supplier of beer storage and dispensing equipment to pub chains and breweries needed to update their self-tilting beer stillage design to maximize the yield from a beer barrel. A self-tilting stillage automatically tilts a barrel as its contents are used so that the sediment (ullage) occupies the smallest volume at the bottom of the cask. This reduces the amount of beer lost in ullage.

A Gas Spring With a Stainless Steel Operating Rod was integrated into the updated design of this self-tilting beer stillage.

The original stillage design consisted of a cradle, pivoted to the unit's base and located by a simple steel coil spring, but it had no natural damping. A full cask was laid on the frame, completely compressing the spring. As beer was drawn off, the spring slowly expanded to produce the required tilting action. If a staff member inadvertently knocked the barrel, it would gently oscillate, disturbing the sediment in the cask and increasing wastage.

To overcome this problem, extremely high damping was needed while retaining the effect of the coil spring. This would ensure that the stillage provided an almost imperceptible tilting action as the barrel emptied. In addition, a universal design was needed so that it would be suitable for cask sizes from 9 to 22 gallons. The operating environment was also an important consideration: The average British pub cellar is cold and damp for conditioning beer and an occasional spill of beer requires equipment to be hosed down.

To meet these requirements, a gas spring with a stainless steel operating rod was selected to ensure maximum corrosion resistance. The gas spring also had a self-lubricating action. For added protection, the manufacturer incorporated a molded, bellows-shaped sleeve into the design to accommodate the gas spring's stroke.

In operation the stillage will start to tilt after approximately a gallon has been drawn off a 9-gallon barrel, while an equivalent 18-gallon cask will be half empty before it begins to move. In a series of trials, this latest tilting stillage design was evaluated against its principal competitor and consistently achieved a 99.5% yield.

More Information
For more information on the type GS 2576-1 gas spring used in this application, contact Brant Pelton, general manager of International Gas Spring (IGS, Crest Hill, IL), at sales@internationalgassprings.com or (800) 214-7034. Visit IGS online at http://info.ims.ca/5215-332. Learn more about Kayel Engineering (Horsham, West Sussex, England) online at http://info. ims.ca/5215-333.