Perforated Metal Sheet Hole Pattern Guide for RFQs

Updated: 2026-10-28

Specify the hole shape, hole size and center-to-center pitch together with the row arrangement. A round hole diameter alone cannot determine open area: 6 mm holes on 10 mm centers give about 32.6% theoretical open area in a 60° staggered pattern, versus 28.3% in straight rows on equal square pitch. Blank margins then reduce the whole-panel opening percentage.

Start with the hole pattern

Perforated sheet buyers often begin with a short phrase such as "round hole sheet" or "perforated panel." That is a starting point, not a full RFQ. The hole shape, hole size, pitch, stagger, margin and sheet thickness should be reviewed together.

If the drawing includes a pattern note, send the exact wording. If the buyer does not have a drawing, a sketch with hole size, center-to-center pitch, sheet size, material and quantity can help QY identify missing details before quotation.

For product context, see perforated metal sheet and expanded metal mesh. For a related comparison, see expanded metal vs perforated sheet.

Hole pattern details buyers should define

RFQ detail	Why it matters	What buyers should send
Hole shape	Defines tooling and pattern review	Round, square, slotted, hexagonal or drawing-specified shape
Hole size	Affects open area and appearance	Diameter, slot width and length, or drawing note
Pitch and stagger	Controls spacing and open area	Center-to-center pitch, straight pattern or staggered pattern
Sheet thickness	Affects material and fabrication review	Thickness or gauge with material
Sheet size	Affects cutting and packing	Width, length, tolerance and piece quantity
Margin or border	Affects usable area and fixing	Unperforated edge, frame area, fixing holes or no-margin request
Finish	Affects corrosion and appearance discussion	Galvanized, painted, powder coated, anodized, stainless or project-specified finish

Calculate pattern open area before comparing quotations

Use the same units for hole diameter d and pitch p. Pitch is measured center to center, not across the clear metal bridge. For adjacent round holes, bridge width is p − d; in the example it is 10 − 6 = 4 mm. State the arrangement on the drawing, since “6 × 10” alone does not identify it.

The formulas follow the area of one circle divided by its repeating cell area, multiplied by 100. For triangular pitch the cell is √3 × p² / 2; for equal square pitch it is p². The rounded constants below apply only to these two arrangements. Use a separate drawing-based calculation for unequal pitches, slots or other patterns.

Round-hole arrangement	Theoretical open area (%)	Example: d = 6 mm, p = 10 mm
60° staggered, triangular pitch	90.69 × (d / p)²	32.6%
Straight rows, equal square pitch	78.54 × (d / p)²	28.3%

Pattern percentage and whole-panel percentage use different areas

Pattern open area excludes blank regions. To estimate the percentage over the complete panel, multiply pattern open area by perforated-zone area divided by total panel area. Hypothetical example: a 1,000 × 1,000 mm panel with an assumed 900 × 900 mm patterned zone gives 32.6484% × 0.81 ≈ 26.4% over the whole panel. This is a layout estimate: actual edge holes and interrupted patterns must be counted from the finished drawing for an exact result.

Write both the pattern percentage and its area basis in the RFQ. Add sheet material and thickness, finished dimensions, blank margins, pattern orientation, tolerances and quantity. Geometry alone does not verify airflow, pressure drop, filtration, strength or machine-guard safety; those need the actual product and project criteria.

Terminology and the perforated-area denominator follow Europerf.

RFQ checklist

Before sending a perforated metal sheet RFQ, prepare:

• Application or project use.
• Hole shape.
• Hole size, slot size or drawing note.
• Pitch, stagger, spacing or open area requirement.
• Material and sheet thickness.
• Sheet width, length and quantity.
• Margin, border, fixing holes or no-margin request.
• Flat sheet, cut-to-size piece, panel or fabricated part requirement.
• Finish or coating request.
• Packing, marks and loading request.
• Destination.
• Drawing, sketch, sample photo or previous order reference.

Related QY pages

• Perforated metal sheet for the main product page.
• Expanded metal mesh for another open-area sheet option.
• Expanded metal vs perforated sheet for product comparison.
• Wire mesh opening and wire diameter for related opening terminology.
• Contact QY Metal Tech when pattern details and drawings are ready.

FAQ

What details are needed for a perforated metal sheet RFQ?

A perforated sheet RFQ should include hole shape, hole size, pitch or stagger, material, thickness, sheet size, margin or border requirement, finish, quantity, packing and destination.

How is open area confirmed for perforated sheet?

Confirm hole shape, size, center-to-center pitch and row arrangement. Calculate theoretical pattern open area using the matching geometry, then distinguish it from the percentage over the whole panel after blank regions. Use the finished drawing and actual hole area when an exact value is required.

Can QY quote perforated sheet without a drawing?

QY may start a preliminary review from hole shape, hole size, pitch, material, thickness, sheet size, finish, quantity and destination. A drawing or sketch is recommended when margin, fixing holes or open area matter.

Is perforated sheet always better than expanded metal?

No. Perforated sheet and expanded metal should be compared by application, pattern, open area, appearance, thickness, edge condition, finish and project requirement.