Bonded Edge Screens for Rotex-Style Screeners: How They Work and How to Reorder the Right One

On a round vibratory separator, a replacement screen drops into a frame and clamps down. On a gyratory ("Rotex-style") screener, the screening surface is a flat, rectangular panel — and the thing that defines that panel is not just the mesh in the middle. It is the edge. A bonded edge screen is a panel of woven wire cloth whose perimeter is bound and reinforced — most commonly with a bonded border — so the cloth seats cleanly in the deck and holds up where it takes the most abuse: the edges. Get the edge, the mounting, and the mesh right, and the panel reorders cleanly. Get them wrong and it either won't seat in your machine or won't last.

This guide is written for the maintenance tech or plant engineer who runs a gyratory screener and needs to understand a bonded edge screen well enough to reorder the right one the first time.

What a Bonded Edge Screen Actually Is

Start with the name, because the name tells you what matters. A bonded edge screen is defined by its edge: the border of the woven cloth is encapsulated and reinforced with a binding material — the "bond" — that wraps the perimeter, keeps the weave from unraveling, and protects the high-stress zone where the cloth meets the deck. The mesh in the center does the screening; the bonded edge is what lets that mesh survive and mount in a gyratory machine.

This is a different idea from a round-separator pre-tensioned screen, where wire cloth is bonded across a full circular frame ring under factory tension. On a bonded edge screen, the bond is at the border of a flat rectangular panel, and the panel is held flat in the deck by its mounting hardware rather than by a rigid factory frame. Both use the word "bonded," but they are not the same product — a distinction worth keeping straight when you reorder.

Why Gyratory Screeners Use a Flat Bonded Panel

Gyratory screeners — the rectangular, long-deck machines often referred to by the Rotex brand — do not move like a round separator. Their motion is gyratory reciprocating: roughly circular at the feed end to spread and stratify the bed, elliptical through the center for high-capacity conveyance, and a straight reciprocating stroke at the discharge to clear near-size particles. The action stays largely in the horizontal plane with very little vertical throw, which is a fundamentally different action from a round vibratory separator driven by top-and-bottom counterweights — a contrast worth understanding when you compare a gyratory sifter to a vibratory screener.

Because the deck is long and nearly flat and the throw is gentle, the cloth has to be held flat and tight by the panel itself, not by aggressive vertical vibration. That is the whole job of the bonded edge plus the panel's mounting and internal reinforcement: keep a wide span of cloth lying flat, seated evenly, and supported so it does not bow, slap, or fray at the border.

How the Panel Mounts — the Machine Decides

A bonded edge screen does not mount the same way on every machine. How the panel is held in the deck depends on the screener, so this is one of the first things to identify before you order:

• Grommets (Rotex-style gyratory). Stainless-steel grommets are set into the bonded border and secure the panel into the deck. This is the common arrangement on Rotex-style machines, and the grommets are part of the spec — type and placement matter.
• Hooks (round/side-tensioned machines). Some machines use a formed hook strip edge that the machine tensions, rather than grommets. A hook edge can itself be bonded for reinforcement.
• Looped or stapled edge (sifter boxes). Flour-mill and box-style sifters often use a looped or stapled cloth edge, sometimes on a wooden or cartridge carrier.

The takeaway: the mesh can be identical across two panels, but if one is grommeted for a gyratory deck and the other is hooked, they are not interchangeable. Confirm how your deck holds the panel before you order.

Edge Types: Bonded, High-Temp, Vinyl, U-Bind

"Bonded edge" is the general category, but the binding material can vary with the application, and the edge type is part of the spec:

• Bonded. The general-purpose bound border — a reinforced edge that protects the cloth and gives a clean, consistent perimeter to seat in the deck.
• High-temperature (Nomex). A high-temperature bonding material for elevated-temperature service where a standard edge would not hold up.
• Vinyl. A washable plastic edge often chosen for clean, frequently-sanitized duty.
• U-bind. A bound tape edge wrapped around the perimeter of the cloth.

The binding also has a width — the band of edge material around the panel — which is captured alongside the edge type when the panel is specified.

Reinforcement and Self-Cleaning: Center Strips, Laterals, and Ball Decks

A wide bonded panel often carries internal reinforcement so the cloth does not flex itself to death across an open span:

• Center strips and laterals. Reinforcing strips run across the panel to support the mesh — center strips along one direction, laterals across the other. Laterals in particular help shield the cloth from wearing against the walls of a ball tray. Depending on the application, a panel may have centers only, or centers and laterals.
• Ball deck (self-cleaning). Pockets beneath the cloth hold rubber balls; the gyratory motion makes them bounce against the underside and knock out particles that would otherwise blind the openings — a common choice for sticky or near-size material.

If your worn panel has reinforcement strips or a ball-deck setup, those are part of what you are ordering — not extras you can leave off and expect the same result.

Mesh Alone Is Not the Whole Spec

The single most common ordering mistake is treating mesh count as if it defined the screen. Mesh count is simply the number of openings per linear inch of cloth. The actual opening — and the open area that controls throughput — also depends on the wire diameter:

• Opening size = (1 ÷ mesh count) − wire diameter. A 10-mesh cloth woven with 0.035" wire has an opening of (1/10) − 0.035 = 0.065".
• Open area % = [opening ÷ (opening + wire diameter)]² × 100. A 30-mesh cloth with a 0.0235" opening and 0.0099" wire runs about 49.5% open area.

Two panels of the same mesh, woven in different wire diameters, give you different openings, different open area, and different wear life. That is why the cloth is specified by mesh and wire diameter together, alongside the alloy.

A Note on Materials

Most bonded edge panels use woven stainless screen cloth, with 304 stainless the common default and 316 preferred for wet or chemically aggressive duty. Grommets and hardware are stainless as well rather than synthetic. Non-metallic media exist for some applications, but the cut precision of a fine woven cloth is the reason most of these panels are wire. The right alloy is a wear-and-chemistry decision, and it belongs in the spec alongside the dimensions.

How to Reorder the Right Bonded Edge Screen

Here is what a supplier needs to build the correct replacement panel:

1. Machine make and model — from the nameplate — and confirmation that it is a gyratory / Rotex-style deck.
2. Panel size — the overall length × width of the panel, including its bonded border.
3. Mesh and wire diameter — captured together, for the reasons above.
4. Alloy — typically 304 or 316 stainless.
5. Edge type and binding width — bonded, high-temp (Nomex), vinyl, or U-bind, and the width of the edge band.
6. Mounting — grommets (and their type), a hook edge, or a looped edge.
7. Reinforcement and anti-blinding — center strips, laterals, and whether the panel runs a ball deck.

Now the part that matters most on the plant floor: do not trust the numbers you read off a worn, installed screen. Wear and stretch distort the opening, and mesh count alone is never sufficient anyway. The reliable moves are to give the machine make and model, or to send the old panel in as a physical sample so the cloth, edge, and construction can be matched exactly. Sending the old part in is the surest path to an exact replacement.

Not sure of your spec at all? You do not have to derive it. Tell the supplier what you are screening, the size you are trying to hit, and the machine you are running, and the cloth, edge, and construction can be recommended from there.

The Bottom Line

A bonded edge screen lives or dies at its border. The bonded edge protects the cloth where it takes the most stress and gives the panel a clean way to seat and mount in a gyratory deck — but it also means a correct reorder is about more than mesh. The panel has to match your machine in size, mounting, edge type, reinforcement, and anti-blinding setup, on top of the mesh and alloy. Capture those, and when in doubt, send the old panel in. That is how you avoid the most expensive screen of all: the wrong one, sitting in a crate during a shutdown.

Frequently Asked Questions

What is a bonded edge screen?

It is a flat, rectangular screen panel whose perimeter is bound and reinforced with a bonded border. The bonded edge keeps the woven cloth from unraveling, protects the high-stress border where the cloth meets the deck, and gives the panel a clean edge to seat and mount in a gyratory ("Rotex-style") screener. The mesh does the screening; the bonded edge is what lets that mesh mount and survive in the machine.

Is a bonded edge screen the same as a round separator's pre-tensioned screen?

No. On a round separator, a pre-tensioned screen has wire cloth bonded across a full circular frame ring under factory tension. A bonded edge screen is a flat rectangular panel whose border is bonded, and it is held flat in a gyratory deck by its mounting hardware. Both use the word "bonded," but they are different products for different machines.

How does a bonded edge screen mount on a Rotex-style machine?

Most commonly with stainless-steel grommets set into the bonded border that secure the panel into the deck. Other machines use a hook edge or a looped edge instead, so the mounting is part of the spec — a grommeted gyratory panel and a hooked panel are not interchangeable even at the same mesh.

What edge types are available?

Common edge types are a standard bonded edge, a high-temperature (Nomex) edge for hot service, a washable vinyl edge for sanitary duty, and a U-bind tape edge. The binding also has a width — the band of edge material around the panel — which is specified along with the edge type.

What are center strips and laterals?

They are reinforcing strips that run across a bonded panel to support the cloth over a wide span — center strips in one direction, laterals across the other. Laterals also help protect the mesh from wearing against the walls of a ball tray. Depending on the application, a panel may have centers only, or both centers and laterals.

Why does mesh count alone not tell me the screen's cut?

Mesh count is just the number of openings per inch. The actual opening is (1 ÷ mesh count) minus the wire diameter, and the open area that drives throughput depends on both numbers. Two panels of the same mesh in different wire diameters have different openings, different open area, and different wear life — so the cloth is always specified by mesh and wire diameter together.

Order the Right Bonded Edge Screen the First Time

ScreenerKing supplies bonded edge screens for gyratory and Rotex-style screeners — in the edge type, mesh, and alloy your application needs. Send us your machine make and model, send the old panel in as a sample, or simply tell us what you are screening and the size you are after, and we will spec it for you. Online ordering for these screens is coming soon — for now, call 866-265-1575 or reach us through the contact page for a quote.