Filter Cage RFQ And Drawing Checklist: Diameter, Wire, Ring Spacing

Why Filter Cage RFQ Details Matter Before A Quote

A filter cage, also called a dust collector bag cage, is the support frame installed inside a dust collector filter bag. When a buyer requests a replacement cage, a quotation can slow down if the request only says "filter cage" or includes one unclear photo without dimensions, top style, bottom style, wire details, or matching bag information.

For a practical filter cage RFQ, the most useful information is clear and measurable: cage diameter, overall length, wire diameter, number of vertical wires, ring spacing, top style, bottom cap style, venturi requirement if used, material or surface treatment if known, matching filter bag size, quantity, and drawings or photos.

This guide helps buyers prepare information before requesting a filter cage quotation. It is not a fit guarantee, coating selection rule, corrosion review, baghouse performance guarantee, or replacement approval from photos alone. Final review should be based on the actual cage, filter bag, dust collector, installation details, and working conditions.

Quick RFQ Checklist Before Requesting A Filter Cage Quote

Before sending an inquiry, prepare as many of these details as possible:

• Cage outside diameter.
• Overall cage length.
• Wire diameter.
• Number of vertical wires.
• Ring spacing and number of support rings.
• Top style, such as top cap, collar, flange, open top, or venturi.
• Bottom style, such as flat cap, round cap, closed bottom, or open bottom.
• Whether the cage is one-piece or split type.
• Material or surface treatment if known.
• Matching filter bag diameter, length, top style, and bottom style if available.
• Dust collector model, tube sheet hole size, or installation photos if available.
• Quantity.
• Drawing, old sample, previous purchase record, or clear photos.
• Current problem, such as bent cage, corrosion, broken welds, poor fit, or bag abrasion.

If some details are unknown, mark them as unknown instead of guessing. Clear unknowns are usually easier to review than guessed dimensions or guessed cage styles.

To request a filter cage quotation, please share the cage diameter, length, wire diameter, vertical wire count, ring spacing, top and bottom style, material or coating if known, quantity, and any drawings or photos available.

Cage Diameter And Overall Length

Diameter and length are usually the first details needed for a replacement cage review. If the old cage is bent, corroded, or worn, measure carefully and explain that the sample is used or damaged.

Diameter Details To Send

Useful diameter details include:

• Outside diameter of the cage body.
• Diameter measured at more than one point if the cage is bent or deformed.
• Matching filter bag diameter if known.
• Tube sheet or cell plate hole size if available.
• Photos showing the measuring tape across the cage diameter.

Do not assume the cage diameter only from the filter bag name or a rough photo. A small mismatch can affect installation review, so actual measurements are helpful.

Length Details To Send

Useful length details include:

• Total cage length from top connection area to bottom end.
• Length of each section if the cage is split type.
• Top cap, venturi, or collar height if it changes the total length.
• Bottom cap height or special bottom structure if visible.
• Matching filter bag length if known.

If the cage has a venturi, extended top, or special bottom cap, send close photos and note whether the measurement includes those parts.

Wire Diameter, Vertical Wires, And Ring Spacing

The cage structure should be described clearly before quotation review. Wire diameter, vertical wire count, and ring spacing help the supplier understand the existing cage design and replacement request.

Wire And Vertical Wire Information

When possible, provide:

• Wire diameter.
• Number of vertical wires.
• Whether the vertical wires are evenly spaced.
• Photos of the wire layout and any welded areas.
• Notes if wires are broken, loose, corroded, or deformed.

This information helps quotation review, but it should not be used as a claim about weld strength, service life, or baghouse performance.

Ring Spacing And Support Ring Information

Useful ring details include:

• Distance between support rings.
• Total number of rings.
• Ring diameter if different from the cage body.
• Any special reinforcement or joint position.
• Photos showing ring spacing with a measuring tape.

If ring spacing is not consistent, send several measurements and mark which section each measurement comes from.

Top Style, Venturi, And Bottom Cap Details

Top and bottom styles are common sources of replacement confusion. A cage may have the correct diameter and length but still need review if the top cap, venturi, collar, flange, or bottom cap is different from the original cage.

Top Style Or Venturi

Useful top details include:

• Top cap, collar, flange, open top, or other visible top style.
• Venturi requirement if the old cage uses one.
• Venturi height, opening diameter, and connection details if measurable.
• Photos taken from the top, side, and inside if safe.
• Matching filter bag top style, such as snap band, ring, cuff, or flange if known.

If the top style is hard to name, do not force a product term. Send photos and mark the style as unknown.

Bottom Cap Or End Style

Useful bottom details include:

• Flat cap, round cap, closed bottom, open bottom, or other visible style.
• Bottom cap diameter and height if relevant.
• Welded bottom structure if visible.
• Photos taken straight at the bottom and from the side.
• Matching filter bag bottom style if known.

Buyers can also review dust filter bag top and bottom style information when preparing bag and cage details together.

Material, Surface Treatment, And Working Conditions

Some buyers know the cage material or coating from previous orders, drawings, or plant records. Others only have an old sample. Either way, material and surface treatment should be described carefully and reviewed with the actual working conditions.

Information that can help includes:

• Carbon steel, galvanized steel, stainless steel, or another specified material if known.
• Coating or surface treatment if known.
• Working temperature if available.
• Dust type and moisture condition if available.
• Gas condition or corrosion concern if already known.
• Current problem, such as rust, corrosion, deformation, abrasion, or difficult installation.

This guide does not confirm corrosion resistance, coating suitability, high-temperature suitability, or service life. For critical conditions, send the working condition details and project requirements for separate review.

Matching The Cage With The Filter Bag

The cage and filter bag should be reviewed together. A replacement cage request is clearer when the buyer also sends the matching filter bag size, top style, bottom style, and installation information.

Helpful matching details include:

• Filter bag diameter and length.
• Filter bag top style.
• Filter bag bottom style.
• Bag material if known.
• Dust collector model or tube sheet information if available.
• Photos of the cage and bag together if available.

Photos can help identify missing information, but they do not replace dimensions, drawings, or sample review when the structure is unclear.

Photos, Drawings, Samples, And Unknown Information

Photos and drawings can reduce back-and-forth, especially when the buyer does not know the exact cage specification.

Useful photos and files include:

• Full cage side view.
• Cage next to a measuring tape.
• Diameter measurement close-up.
• Overall length measurement close-up.
• Top cap, venturi, or collar close-up.
• Bottom cap close-up.
• Wire and ring spacing close-up.
• Damaged, bent, corroded, or worn areas.
• Matching filter bag photos.
• Dust collector nameplate, tube sheet, or installation position if available.
• Drawing, old sample, previous supplier specification, or previous order record.

If the drawing is incomplete, send it anyway and mark the missing details. If the old cage is damaged, explain which measurements may be affected.

FAQ

What Information Is Needed For A Filter Cage RFQ?

A useful filter cage RFQ usually includes cage diameter, overall length, wire diameter, number of vertical wires, ring spacing, top style, bottom style, venturi requirement if used, material or surface treatment if known, matching filter bag size, quantity, and photos or drawings.

How Do I Measure A Replacement Filter Cage?

Measure the outside diameter, total length, wire diameter, ring spacing, and top and bottom structure. If the cage is bent or damaged, measure several points and send photos showing the damaged areas. Mark uncertain measurements clearly instead of guessing.

What Wire And Ring Spacing Details Should I Provide?

Provide wire diameter, number of vertical wires, ring spacing, total number of rings, and photos of the wire and ring layout. If ring spacing changes in different sections, list each measurement separately.

What Top And Bottom Style Details Are Important?

Send photos and measurements of the top cap, venturi, collar, flange, or open top, plus the bottom cap or end style. Also provide matching filter bag top and bottom style information if available.

Can I Request A Custom Filter Cage Without A Complete Drawing?

A request can be reviewed when the buyer provides enough dimensions, photos, matching bag details, working conditions, and quantity. A complete drawing is helpful, but if it is not available, clear photos, measurements, and an old sample can support the review. This does not mean every cage can be confirmed from photos alone.

Requesting A Filter Cage Quotation

A clear cage RFQ should help the supplier understand the cage structure, filter bag match, dust collector connection, and working conditions before review.

When you request a filter cage quotation, please share:

• Cage diameter and overall length.
• Wire diameter and number of vertical wires.
• Ring spacing and number of support rings.
• Top style and bottom cap style.
• Venturi details if used.
• Material or surface treatment if known.
• Matching filter bag diameter, length, top style, and bottom style.
• Dust collector model or tube sheet information if available.
• Quantity.
• Photos, drawing, old sample, or previous purchase record.

For broader quotation preparation, buyers can review RFQ guides for filter bags, housings, cartridges, cages, and air filters before sending related details.

For related product information, buyers can review filter cage, dust filtration products, dust filter bags, dust collector filter bag measurement guidance, and dust filter bag top and bottom style guidance. For quotation support, contact SFFILTECH.