Collar Rings for Filter Sleeve Cages: small components, big impact on filtration

When discussing the performance of a baghouse, attention often goes to the filter sleeves and the Venturi. Yet there is a “quiet” component that decisively affects sealing, durability, and operating stability: the collar ring. Positioned at the top of the cage, the collar consistently connects the cage, tubesheet, and filter sleeve, ensuring alignment, mechanical support, and the correct seating of the sleeve. In other words, it’s the point where design turns into day-to-day reliability.

Why the collar matters so much

A well-designed collar ring:

• ensures a secure fit between sleeve and cage, preventing micro-movements that cause cuts or abrasion on the fabric;
• stabilizes the inlet geometry, helping the pulse wave propagate correctly along the sleeve and supporting smooth, predictable operation over time;
• reduces wear on edges and contact points, extending the service life of both sleeve and cage;
• simplifies installation and maintenance, thanks to seats and lips engineered for quick, repeatable fitting and release.

Over the long term, this translates into fewer cleaning pulses, lower compressed-air consumption, fewer stoppages, and greater production continuity.

Materials and finishes: choose for the environment

CleanAir’s range uses high-quality raw materials and technologies aligned with industry standards. Collars are produced in:

• plain carbon steel, an essential and cost-effective solution for dry, non-corrosive areas;
• pre-galvanized steel, providing basic protection against humidity and oxidation;
• stainless steel, ideal where condensate, washdowns, or chemically aggressive atmospheres are present.

Surface finish is often underestimated: chamfered edges and smooth surfaces limit the risk of micro-cuts on the fabric, improve hygiene (useful in food & beverage), and support a cleaner cake release during pulse-jet cleaning.

Available types: form meets function

To adapt to different layouts and fastening methods, we offer five families (available in multiple sizes):

• Collar A – band with high groove
  Provides a deep, stable seat for the sleeve connection—particularly useful when maximum mechanical sealing is required or when assembly tolerances must be compensated.
• Collar B – open band with inner lip
  The opening slot eases installation; the inner lip guides and locks the sleeve in position, limiting rotation and misalignment.
• Collar C – flat-flange
  A simple, versatile geometry that promotes even bearing on the tubesheet. Often chosen to standardize spares across heterogeneous plants.
• Collar D – rounded flange
  The soft profile reduces point stresses on the fabric and the risk of abrasion over time. Recommended where media durability is a priority.
• Oval Collar D – rounded flange (for oval cages)
  Designed for space-saving installations or to increase filtration area without changing the housing. It retains the sliding and protection advantages of the round version.

Each type is available in a wide dimensional range to match round, oval, or star cages and different sleeve fastening systems.

Customization: a collar ring tailored to the process

Beyond the catalog range, CleanAir manufactures custom collars to customer specifications. When does it make sense to customize?

• Non-standard tubesheets or retrofits on existing filters where legacy dimensions must be maintained;
• Special filter media (pleated, membrane, anti-stick finishes) that require dedicated bearing profiles;
• Process needs (high temperature, condensate, aggressive chemistry) calling for specific thicknesses, materials, or finishes;
• Fast turnarounds: lines with frequent sleeve replacements benefit from “guided” geometries that speed up downtime.

Customization can involve material, thickness, edge profile, lips, and seats, up to integrating identification elements for traceability and more efficient maintenance.

Collars within the filter system: one coordinated design

The collar never works “alone”: its effectiveness depends on its coherence with the cage, sleeve, Venturi, and accessories (bottom caps, rings, joints). Proper pairing:

• promotes uniform cleaning along the entire sleeve;
• avoids inlet bottlenecks that hinder flow;
• reduces micro-abrasion and wear initiation points;
• keeps the filter’s behavior stable across different operating conditions (startups, transients, load changes).

That’s why, during design or revamping, it’s useful to evaluate the collar together with the rest of the package: often a simple upgrade in profile or material yields immediate benefits in reliability and compressed-air consumption.

Packaging and logistics: protecting value all the way to site

A perfectly made collar can lose effectiveness if it arrives on site damaged. Alongside manufacturing, CleanAir provides dedicated industrial packaging (custom wooden crates/cages, anti-shock and anti-corrosion protection) and careful shipping processes. The goal is to ensure components arrive in pristine condition, ready for installation—reducing delays, rework, and disputes.

The collar is a small yet critical component: its geometry determines sealing, operational stability, and the service life of the entire filtration system. With a complete range—plain steel, pre-galvanized, stainless; five types; multiple sizes—and the option of made-to-order designs, CleanAir offers the right combination for every filter and every process. Choosing the proper collar means protecting the sleeve, enhancing the cage, cutting air consumption, and making filtration more efficient, predictable, and sustainable.