Vent Panels

Think Schlegel EMI for Shielding – Honeycomb Vent Panels

As the originator of the fabric-clad foam EMI shielding technology, Schlegel EMI is the industry’s most trusted name. We continue to set the standard for quality and innovation, designing advanced solutions for a wide range of applications. And our worldwide locations ensure that you get what you need, when you need it.

Modern electronic equipment often requires EMI Gaskets to avoid radiating EMI/RFI suspeptibility to outside sources of EMI/RFI. Maintaining electromagnetic compatibility can be an increasing challenge of the designers of today’s electronic and electrical products.

Schlegel Electronic Materials, Inc. (SEM), the preeminent manufacturer of fabric over foam EMI shielding products for the computer, telecommunications, and electronic industries, offers a full range of EMI shielding products–including gaskets, I/O backplane shielding gaskets, and highly conductive envelopes, tapes and laminates. SEM is now proud to introduce a complete line of quality honeycomb vent panels. The addition of vent panels to SEM’s extensive portfolio of shielding products allows SEM to be your exclusive EMI shielding supplier, to help you meet or exceed yur global requirements for electromagnetic compatibilty (EMC).

We use 5052 grade aluminium foil which is a lightweight material offering superior strength and corrosion resistance over commercial grade aluminium foils. It meets all the requirements of MIL-C- 7438. This material is used to manufacture aircraft floors & wing edges, missile wings, helicopter rotor blades etc, so quality and repeatability is assured. Currently we have 7 frame styles available. To keep down production cost, vent panels made with styles 1701, 1703, 1705, 1706 & 1707 are normally supplied with 3 corners notched and the 4th joined corner welded. If required, all 4 corners of the panel can be supplied fully welded. Frame styles 1702 & 1704 are always supplied with fully welded corners.

All frame stylescan be supplied with a conductive gasket to provide the best electrical contact between the frame and mating metal surface.

Standard tolerances for overall Finished Vent Dimensions are +/- 0.8mm
Standard tolerances on Hole Centres are +/- 0.4mm
Typical corner radii on frame styles 1701, 1703, 1705, 1706 & 1707 are R3.0mm

The standard finish for aluminium vent panels is SemPas , it fully meets the RoHS directive and replaces Alocrom 1200. This in-house process applies a permanganate passivation which is a chromate free, inorganic and non toxic coating. The process produces a dense, uniform coating consisting of aluminium and reduced manganese oxides giving a golden yellow colour to the surface. The surface finish is conductive with a low contact resistance equalling Alocrom 1200. It also meets all requirements of MIL-C-5541E for corrosion and electrical conductivity


Aluminium Honeycomb Sizes and Styles

Standard straight cell sizes & thickness held in stock are:

3.2mm (0.125″) cell x 12.70mm (0.50″) thick
3.2mm (0.125″) cell x 6.35mm (0.25″) thick
1.6mm (0.0625″) cell x 6.35mm (0.25″) thick
3.2mm (0.125″) cell x 3.2mm (0.125″) thick

Standard slant cell sizes, angles & thickness held in stock are:

3.2mm (0.125″) cell x 6.35mm (0.25″) thick x 30°
3.2mm (0.125″) cell x 6.35mm (0.25″) thick x 45°

Frame styles 1702 & 1703 are supplied fitted with solid monel mesh EMC gasket as standard. Tinplated Copper Clad Steel (TCS), Aluminum or Stainless Steel solid mesh can also be specified if required. All other frame styles can be supplied with many different types of EMC gaskets including knitted mesh bonded to an environmental seal, oriented wires in silicone, conductive fabric over foam or beryllium copper.

Kick Plates
For high traffic areas or where honeycomb damage could easily occur kick plates can be fitted. Two types are stocked as standard, however custom designs to customers specific requirements (i.e louvred openings) can be discussed and fitted if requested.

Expanded Aluminium Style

Provides maximum protection but reduced airflow
Woven Stainless Steel mesh

Provides lower protection but with better airflow

Vents are normally supplied with drilled clearance holes to customer specific sizes. Inserts are also offered and are stocked in M3, M4 & M5 sizes. Other styles and sizes are available on request. Standard tolerance on Hole Centres is +/- 0.4mm.
Centre Bar Extrusion
Where a vent panel is very large, we can fit a centre strengthening extrusion to provide additional mechanical rigidity to the vent panel. Used with outer frame styles 1701/1702/1703/1704 & 1707 only.

Pressure Drop and Shielding Performance

Honeycomb Type

Frequency Field Type 1 Type 2 Type 3 Type 4 Type 5 Type 6
 200kHz H 66 39 65 71 71  78
 100MHz E 105 80 105 105 105 100
 500MHz P 81 55 50 93 93 55
 2GHz P 85 52 60 94 94 96
 10GHz P 85 61 72 82 90 80


 Type 1 2 layers 3.2 cell x 3.2mm thick honeycomb (total 6.4mm)
 Type 2 1 layer 3.2 cell x 6.35mm thick honeycomb
 Type 3 1 layer 1.6 cell x 6.35mm thick honeycomb
 Type 4 2 layers 3.2 cell x 6.35mm thick honeycomb (total 12.7mm)
 Type 5 1 layer 3.2 cell x 6.35 thick honeycomb +1 layer 3.2 cell x 6.35mm
 thick slant honeycomb (total 12.7mm)
 Type 6 1 layer 3.2 cell x 12.7mm thick honeycomb

Honeycomb Combinations

Frame Style Type 1 Type 2 Type 3 Type 4 Type 5 Type 6

All of the above frame styles and honeycomb combinations are available with the option of a stainless kick-plate.