Metal Tellerette Ring

A metal Tellerette ring is the metal version of the garland, or flower-ring, packing. Like the plastic rosette it is built from twelve small rings set in a radial pattern, so the finished piece is an open, flower-shaped body with plenty of gaps; unlike the plastic kind, it is formed and welded from thin metal strip. That single change, metal instead of plastic, is what defines it. The metal holds the open rosette shape under heat, cold and mechanical load that would soften or distort a plastic packing, and it lets the piece be very thin-walled, so the void fraction reaches 95 to 98 percent. The open, radial form still does what a rosette does well: it does not jam or clog, and it spreads gas and liquid over a large surface at a very low pressure drop. It is, in short, a rosette packing for duties too hot, too cold or too demanding for plastic.

The ring is made from corrosion-resistant metals, and the choice follows the chemistry, not just the temperature. Stainless steel 304 is the general-purpose grade; 316L, with molybdenum added, resists chlorides and a wider range of acids; titanium is the answer for wet chlorine, seawater and oxidising acids; and nickel alloys cover the most aggressive hot acids. What all of them share, and what plastic cannot match, is the temperature range: a metal Tellerette works from cryogenic cold, around minus 200 degrees, up to about 600 degrees. That is why the metal version is chosen for hot distillation, cold gas separation and other duties that run far outside the roughly 150-degree ceiling of a plastic rosette. Tell us the medium and the temperature and we will name the alloy.

The metal Tellerette earns its place where the service is hot, aggressive or demands purity. In chemical plants it is used for acid absorption and solvent recovery; in petrochemical work for gas scrubbing and distillation; in environmental plants for VOC abatement and wastewater treatment; and in pharmaceutical work for the distillation of high-purity solvents. In each, the draw is the same set of qualities: a very high void that passes a large flow at a low pressure drop, an open shape that resists fouling, and a metal body that stands up to strong acids and to a wide sweep of temperature. Where a column runs hot, cold or clean beyond what plastic allows, the metal rosette is the fit.

Against the two classic rings, the Tellerette leads on openness and fouling. Its void fraction, at 95 to 98 percent, is higher than a Pall ring's 90 to 95 percent and far above a plain Raschig ring's 70 to 80 percent, so its pressure drop is very low where the Pall is low and the Raschig only moderate. On fouling it is better still: the open rosette clogs minimally, where a Pall ring is moderate and a Raschig ring prone to it. And because it is metal, its acid resistance is excellent, set by the alloy, whereas a Raschig ring's is limited and a Pall ring's depends on what it is made from. The trade is cost and a more intricate shape; for a straightforward, low-duty column a Pall or Raschig ring is cheaper. Send the duty and we will help you weigh it.