Electromagnetic Compatibility EMC Components and Gaskets for RFI/EMI Shielding
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Electromagnetic Compatibility EMC Components and Gaskets for RFI/EMI Shielding

Proven EMC Shielding Performance Electromagnetic Compatibility For the latest up to date information and news please visit our web site 19-21 Finch Drive, Springwood Industrial Estate, Braintree, Essex CM7 2SF, United Kingdom. T +44 (0)1376 348115, F +44 (0)1376 345885, E infoOkemtron.co.uk, www.kemtron.co.uk

Exceptional EMC shielding and environmental sealing solutions Kemtron, a leading company in EMC shielding and environmental sealing since 1980, works with blue chip customers in more than 35 countries around the world. We have developed a global reputation for quality, performance and reliability, with an enviable track record in demanding industries such as defence, aerospace, information technology, communications and electronics. We help customers meet their EMC shielding and environmental sealing requirements with innovative solutions that enhance product performance, reduce...

Environmental Sealing Overview Environmental Sealing: Design Tools Conductive Elastomers: Flat Gaskets Sheet & Flat Gaskets Materials Data Form-in-Place Gaskets Oriented Wires In Silicone & Fluorosilicone Rubber Woven & Expaned Wire In Elastomers Conductive Adhesives Knitted Wire Mesh: Overview Solid Knitted Wire Mesh Over an Elastomer Core With an Environmental Seal Conductive Fabric Over Foam Gaskets Beryllium Copper FInger Stock Connector Gaskets for RFI/EMI Shielding EMI Shielding Ventilation Panels: Aluminium Honeycomb Air Ventilation Panels for RFI/EMI Shielding Aluminium Screen EMC...

EMC Components & Gaskets Overview Conductive Elastomers Oriented Wires in Silicone Electrically conductive elastomers are made from silicone or fluorosilicone loaded with highly conductive particles such as silver plated aluminium, silver plated copper, nickel coated graphite and pure nickel. Available as extruded profiles, ‘O’ rings, moulded components, and flat sheet for die cut gaskets. Conductive elastomers offer an excellent temperature range and are resistance to compression set and Fluorosilicone has superior resistance to fuel oils and solvents. Knitted wire mesh gaskets provide an...

EMC Components & Gaskets Overview Beryllium Copper Finger Stock Form-in-Place Gaskets Connector Gaskets Beryllium copper EMI gaskets have superior mechanical spring characteristics and high electrical conductivity making them ideally suited to shielding applications where frequent access is required such as shielded room doors. These are available in profiles to suit most EMI shielding applications including grounding. Many plating finishes are available to address galvanic compatibility concerns and enhance shielding performance. Conductive or non conductive elastomer silicone compounds...

EMC Components & Gaskets Overview Cable Shielding Jackets Conductive Adhesives Zip on type tubing with internal EMI shielding liner for shielding of bundled cables. Easy to open and close so cables can be added or removed. Tubing is available in many diameters and is suitable for static or flexible applications. Flame retardant and low smoke/low toxicity versions are also available. Kemtron’s cable entry gland provides an excellent EMI shield for screened cables which pass through enclosure walls. Made from brass they are available to suit cables from 1.5mm diameter up to 16mm. They also...

Environmental Sealing Overview Flat Gaskets Kemtron stock many types of elastomeric materials for flexible environmental sealing but specialising in silicones, fluorosilicones, solid and sponge that meet UL94V-0 and low smoke/ low toxicity. Other materials include Poron™ polyurethane, Neoprene™/ chloroprene, EPDM etc. Materials can be supplied as sheet, strip, laminated, self adhesive backed or die cut to complex shapes. Liquid RTV silicone can be applied as a form in place gasket direct to customer’s hardware. Flat gaskets can be cut by rule die, kiss cut or more complex shapes by water...

Design Tools What is EMC? The definition of EMC is the measure of equipment’s capability to neither conduct electromagnetic energy nor radiate it. The equipment in turn should not be susceptible to any conducted or radiated emissions from any other source. The two most important characteristics of electromagnetic waves connected with interference are the amplitude and the frequency of the waves. Interference Control The three main ways in which interference factors can be controlled are:- EMI Shielding The EMI shielding of any enclosure involves all of the internal and external openings and...

Electrical The electrical requirements are covered by measurements made to ascertain the level of attenuation required to fulfil the figures laid down in the appropriate specification over a specified frequency band. The data given in the catalogue outlines the typical attenuation versus frequency of the various materials when correctly fitted. These figures are corroborated by independent tests. Mechanical The mechanical considerations are of the utmost importance in the fitment of shielded gaskets. The design of an EMI shielded enclosure should be undertaken as if the gasketing will be...

Design Tools Bi-Metallic Corrosion Because of the number of variables that contribute towards electrolytic or bi-metal corrosion, it is not practical to illustrate all possible situations and therefore the following data should be used for guidance only. If more definitive evidence is required, then we suggest that a test be conducted, employing the materials to be used and analysing the results. As a general rule the less noble metal corrodes leaving the more noble metal intact, for example, if aluminium and silver are in contact in the presence of a suitable electrolyte a current will...

Design Tools Many of Kemtron’s EMC and Environmental products are offered with UL94 flammability ratings. The following chart may prove helpful when deciding the level required. Please note that we can only supply products rated as indicated in the individual data, other ratings are given for convenience. UL94 Flammability Ratings explained 5VA Surface Burn Burning stops within 60 seconds after five applications of five seconds each of a flame (larger than that used in Vertical Burn testing) to a test bar. Test specimens MAY NOT have a burn-through (no hole) This is the highest (most flame...