Metal Cascade Mini Ring

Metal cascade mini ring, also called the step or ladder ring, is an improved Pall ring built low and squat: its height is only about a third to a half of its diameter, and one end is rolled out into a flared collar. That short, flared shape keeps the rings from nesting and helps them tumble into an open, evenly spread bed, so against an ordinary Pall ring it carries 10 to 20 percent more flux, drops the pressure by 30 to 40 percent, and separates a little better as well. It is rolled from carbon steel or from stainless in grades 304, 304L, 316, 316L and 410, so it copes with high heat and strong acids. Void fraction roughly 96 to 98 percent; made in 25, 38, 50 and 76 mm; model RJ-400.

Improved Pall ring, low and squat (height about a third to a half the diameter), with a flared collar.
Open, non-nesting bed: 10 to 20 percent more flux than a Pall ring.
Pressure drop 30 to 40 percent lower, with better separation efficiency.
Carbon steel, or stainless in 304, 304L, 316, 316L and 410; heat- and acid-resistant.
Void roughly 96 to 98 percent; made in 25 to 76 mm; model RJ-400.

Technial Parameters

Size (mm)	Surface area (m²/m³)	Void ratio (%)	Pieces per m³	Dry packing factor (m⁻¹)
25	220	96.5	97,160	273.54
38	154.3	95.9	31,800	185.8
50	109.2	96.1	12,300	127.4
76	73.5	97.6	3,540	81

Property	Value
Product Type	Metal random packing (cascade mini / step ring)
Structure	Low ring (height about ⅓–½ of diameter) with a flared collar; windowed wall
Material	Carbon steel; stainless steel 304, 304L, 410, 316, 316L
Model NO.	RJ-400
Standard Sizes	25, 38, 50, 76 mm
Void Ratio	95.9–97.6%
Surface Area	73.5–220 m²/m³
Dry Packing Factor	81–273.54 m⁻¹
Gain vs Pall ring	Flux +10–20%, pressure drop –30–40%, better separation
Colour	Light grey
Advantages	High flux, low pressure drop, high mass-transfer efficiency, acid and heat resistant
Applications	Decarbonization absorption and regeneration towers; hydrogen production; ammonia/fertilizer synthesis; chemical and petrochemical
Trademark	RONGJIAN
Origin	China
HS Code	8419909000
Transport Package	Carton box / ton bag / steel drum

FAQs

What is a cascade mini ring, and what makes its shape different?

A metal cascade mini ring is a short, low version of the Pall ring, and it is often called the step or ladder ring. Two things set its shape apart. First, it is squat: its height is only about a third to a half of its diameter, where a Pall ring is roughly as tall as it is wide. Second, one rim is rolled outward into a flared collar. Those two features change how the rings pack. Being short, they cannot stack neatly inside one another, so a dumped bed stays open and evenly distributed; and the flared collar spreads the liquid and stops the rings from locking together. The wall itself carries windows with inward tongues, like a Pall ring, to open up the internal surface. The upshot is a more open, better-distributed bed than a plain ring gives, which is exactly where its higher capacity and lower resistance come from.

What does the cascade ring gain over a Pall ring?

The cascade mini ring was designed as a step up from the Pall ring, and the gains are measurable. For the same column it passes about 10 to 20 percent more flux, because its open, non-nesting bed lets more gas and liquid through. It drops the pressure by roughly 30 to 40 percent, because there is less to obstruct the gas. And its separation efficiency improves too, by an amount that depends on the particular process. So a bed of cascade rings can handle more throughput, burn less energy on pressure, and separate at least as well, or be built shorter for the same job. A Pall ring holds only a marginally simpler shape and a lower unit price; for most new or revamped columns, the cascade ring's performance wins. Send your existing Pall-ring column and we will put a number on the improvement.

What steels is it made in, and how well does it resist heat and acids?

Material is a menu, chosen to suit the stream. The cheapest route is plain carbon steel, fine when nothing corrosive is present. For ordinary corrosion the usual answer is austenitic stainless, grade 304 or its low-carbon twin 304L. When chlorides or stronger acids are in play, the molybdenum-bearing grades 316 and 316L earn their keep; and where the packing must also survive abrasion, hardenable 410 is the pick. Every one of these steels does what no polymer can: it keeps its strength and shape in real heat and under aggressive chemistry, so a cascade-ring bed goes on working in hot, corrosive columns for years rather than degrading. That is why the ring is a fixture in continuous, heavy-duty service. Send the medium and its temperature and the steel choice is easy.

Where is a metal cascade mini ring used?

The metal cascade mini ring is used across chemical, fertilizer and oil-refining plants, and it is a favourite in gas decarbonization. A typical duty is the absorption tower and the paired regeneration tower of a carbon-dioxide removal system, for instance in the hydrogen and ammonia sections of a fertilizer works, where the synthesis gas must be scrubbed of CO2 and the solvent then stripped and reused. In those towers the ring's high flux and low resistance cut the energy the process spends on moving gas, while its metal body handles the heat and the chemistry. More broadly it goes into absorption, stripping and washing towers wherever a high-capacity, low-drop metal packing is wanted. Give us the process and the tower dimensions and we will name the ring and the steel.

The metal cascade mini ring, the step or ladder ring, is a Pall ring redesigned to sit low and open. Where a Pall ring is about as tall as it is wide, the cascade ring is squat, its height only a third to a half of its diameter, and one rim is flared outward into a collar. That low, flared shape is where all its gains come from: short rings will not nest inside one another, so a dumped bed stays open and evenly spread, and the flared collar helps distribute the liquid and keep the rings from interlocking. Rolled from stainless or carbon steel, with Pall-style windows and inward tongues in its wall, it is strong, very open, and resistant to heat and acid.

What each feature buys, against a Pall ring:

Design feature	What it does
Low ring height (a third to a half the diameter)	Rings cannot nest, so the bed stays open, about 10 to 20 percent more flux
Flared collar on one rim	Spreads the liquid and stops interlocking, pressure drop about 30 to 40 percent lower
Windowed wall with inward tongues	Opens the internal surface for contact and better separation
Thin stainless or carbon steel	High void with strength and resistance to heat and acids

Those gains put it into high-throughput gas duty everywhere: decarbonization absorption and regeneration towers in hydrogen and fertilizer plants, and absorption, stripping and washing towers across the chemical and oil industries. It comes in carbon steel and in stainless grades 304, 304L, 316, 316L and 410, from 25 up to 76 mm across. To spec a bed, just send us the tower dimensions and what it is running, and we will pick the ring size and steel.