Custom Expanded Metal Filter Tube
An expanded metal filter tube is formed from slit-and-expanded sheet into a cylindrical support, guard or coarse-screening body. A quotation-ready design specifies the diamond geometry, strand, thickness, orientation, tube dimensions, seam, ends and whether a finer filtration layer is added.
Expanded Metal Tube Functions
Structural support
Rigid cylindrical backing behind woven mesh, pleated media or another fine filtration layer.
Protective sleeve
Open metal guard helping protect finer media from handling or mechanical contact.
Coarse screening
Diamond openings retain larger debris where precision filtration is not required.
Drainage layer
Open structure provides flow paths between media and a supporting body.
Expanded Metal Filter Tube Specification Checklist
Do not specify expanded metal only as a diamond size. Pitch and clear opening are different dimensions, and strand width plus thickness determines the remaining metal structure.
| Specification field | What to provide | Design effect |
|---|---|---|
| Opening geometry | SWD/LWD pitch or SWO/LWO clear opening; identify the convention | Defines diamond size, direction and geometric open area |
| Strand and thickness | Strand width, base-metal thickness, raised or flattened condition | Affects stiffness, profile, forming and available flow path |
| Tube geometry | OD or ID, length, roundness and tolerances | Controls equipment fit and media-support clearance |
| Seam and orientation | Longitudinal joint, overlap/weld and diamond direction | Influences continuity, forming and directional stiffness |
| Ends and filter layers | Open/closed ends, caps, collars, flanges, fine media and flow direction | Defines mounting and the complete filtration assembly |
SWD, LWD, SWO and LWO
SWD and LWD describe short-way and long-way pitch, normally center-to-center. SWO and LWO describe corresponding clear openings. The drawing should identify which convention is used.
For formulas and diagrams, use the expanded metal sizes guide and calculator.
Strand, Thickness and Orientation
Strand width is measured across the solid metal ligament. Base-metal thickness is not automatically the same as the final raised profile. Flattening changes surface profile and can alter opening geometry.
Diamond orientation should be shown relative to the tube axis because expanded metal is directionally structured. Forming direction, seam position and support load should be considered together.
Product Examples: Opening and Forming Options
These Maidong material images show representative expanded-metal structures used before or during cylindrical fabrication. Final tube dimensions and edge details are controlled by the approved drawing.
Different opening proportions
Raised diamond structure
Fine expanded sheet for forming
Tube and Composite Configurations
Expanded-only tube
Used where coarse screening or an open structural body is sufficient.
Inner support core
Expanded metal placed inside fine mesh for outside-to-inside differential pressure.
Outer protective sleeve
Expanded layer outside fine media for mechanical protection and handling.
Multilayer assembly
Expanded support combined with woven mesh, Dutch weave or another defined filter medium.
For a perforated-sheet alternative, compare the perforated filter tube. For complete cylindrical elements, review stainless steel filter tubes.
Expanded Metal Tube Selection Workflow
1. Define the function
Support core, protective sleeve, drainage layer or coarse screen.
2. Specify the mesh
State pitch/opening convention, strand width, thickness, condition and material.
3. Define the tube
Provide OD/ID, length, orientation, seam, roundness and tolerances.
4. Add filter layers
Show fine media, layer order, support side and flow direction.
5. Complete the drawing
Include ends, interfaces, operating conditions, quantity and required documents.
Applications by Function
Filter support cores
Cylindrical backing for woven mesh, sintered or pleated filtration media.
Strainers and guards
Coarse screening and protection around process or equipment openings.
Air and gas components
Open support body where pressure loss and structural clearance must be balanced.
Custom fabricated parts
Drawing-based cylinders, sleeves and framed shapes with specified edges and ends.
Expanded Metal Filter Tube FAQ
It is a cylindrical component formed from slit-and-expanded sheet. It is commonly used as a coarse screen, protective sleeve, drainage layer or structural support for finer filter media rather than as a precision filtration medium by itself.
A complete specification distinguishes short-way and long-way pitch (SWD/LWD), clear openings (SWO/LWO), strand width, base-metal thickness, raised or flattened condition and orientation.
Usually not by itself. Its diamond openings are generally used for coarse screening or support. Fine retention normally requires woven wire mesh, Dutch weave, sintered media or another filter layer added to the tube.
State material, raised or flattened condition, opening and pitch dimensions, strand width, base-metal thickness, OD or ID, length, seam, edge condition, ends, tolerances, support direction, quantity and intended function.
Drawing-based tubes can be reviewed with open or closed ends, caps, collars, flanges, frames and other mounting details. Critical interfaces and weld requirements should be shown on the drawing.
Geometric open area can be estimated from clear-opening and pitch dimensions measured under the same convention. Forming, seam overlap, margins, supports and additional filter layers can reduce effective component open area.
Request an Expanded Tube Drawing Review
Send the material, opening convention, strand, thickness, tube dimensions, orientation, seam, ends, filter layers and operating conditions. Maidong can review a custom expanded metal tube enquiry.