Kemtron Ltd

Conductive Elastomers

Kemtron Ltd's electrically conductive elastomer materials are suitable for many customer applications across a wide temperature range. Our conductive elastomers are manufactured from silicone and fluorosilicone and are loaded with highly conductive particles such as silver plated aluminium, silver plated copper, nickel coated graphite and pure nickel. Our conductive elastomers are available in standard and custom configurations including extruded profiles, 'o' rings, moulded components, and flat sheets for die cut gaskets. The properties of our conductive elastomer materials enable resistance to compression, fuel oils and solvents.

Woven Wire Mesh in Elastomers

All electronic equipment emits and receives some form of electrical interference. Our knitted wire mesh gaskets are created to produce high levels of EMI shielding performance in magnetic and electric fields. Our knit meshes are available in the following wire types: monel, stainless steel, solid mesh and tin plated copper clad steel. Knitted mesh gaskets can be supplied as solid mesh or knitted over elastomeric cores with or without environmental seal in continuous lengths or fabricated to custom designs.

Orientated Wires & Silicone Gasket Material

Our solid and sponge silicone variants consist of vertically oriented monel or aluminium wires up to 140/sq cm. They combine excellent EMP survivability with a high level of effective RFI/EMI/EMP shielding. The wires are ideal for use as access panels, seals and connector gaskets and are available as sheet stock, strip or can be die cut to meet customer's individual design requirements. Different materials are available in varying thickness to accommodate most design requirements. Self-adhesive backing and compression stops or collars can be fitted to prevent over compression and fluorosilicone versions are available for use in environments where fuels/oils/ hydraulic fluids and other contaminants are present.

EMI Shielding Ventilation Panels

Our range of EMI shielding vent panels are designed to allow air-flow whilst preventing the  transmission of electromagnetic interference. Our commonly used vent panels are made from aluminium or steel honeycomb panels mounted in an extruded aluminium frame. Honeycomb vent panels are used for applications for high level of air flow and shielding performance such as in heating and ventilation systems, generators, engines and cooling high power systems. Our honeycomb panels are available in a range of thickness to meet different shielding requirements and protective grills are available for vulnerable areas together with dust filtration foams. Many plated or painted finishes can be specified.

Conductive Fabric over Foam Gaskets

Our conductive fabric over foam gaskets are formed by wrapping a conductive fabric such as nickel/copper, silver plated polyester or nylon fabric over an open celled urethane core and are designed for shielding in various electronic enclosures. We supply various profiles such as rectangular, D shape and low compression/deflection C shape seals. These ranges provide excellent EMI gaskets with low compression sets and excellent abrasion resistance for high cycling and wiping applications. Most meet UL94V-0 and are available as strips, cut to length or die cut.

Form in Place Gaskets

We supply conductive and non-conductive elastomer silicone compounds that are deposited as a gasket directly to the enclosure by XYZ CNC technology. The dispensing machine deposits the gasket by following a pre-determined CNC path to provide accuracy and repeatability. This process is advantageous in many ways: materials are one-component room curable, small gasket land is required, there are low set-up costs, no material waste, excellent EMI shielding, it can be applied to metal and plastic components, and more.

Form in place gaskets can be very intricate to suit enclosures with little space for a traditional gasket such as thin walled multi compartment housings providing an EMI and environmental seal.

EMI Shielded Windows

The shielding of optical windows is created by embedding finely woven metal mesh made from fine stainless steel or copper wire mesh. Meshes are made to various sizes and thickness and can be coated and blackened to prevent surface reflections. Shielding and screening of optical windows can also be reached by the application of a transparent vapour deposited conductive coating such as Indium Tin Oxide or Gold to the surface of the optical substrate. Our EMI shielded windows are commonly requested for display services or inspection panels where they provide optimum transparency and EMI shielding.

Conductive Adhesives

We supply high quality single component RTV (room temperature vulcanising) silicone adhesives that are electrically conductive. Our Kembond range of adhesives are available with a range of fillers such as silver and nickel coated graphite which are designed to be used as a thin bond between two components. Caulking compound can also be supplied to fill larger gaps and voids, surface imperfections or to hold conductive gaskets in position. Our Kembond RTV adhesives are available in standard manual or pneumatic 10ml syringe barrels for direct application. We also supply two component electrically conductive epoxy adhesives for use with most common substrates.

Ferrites for EMI Suppression

Kemtron are specialists in stocking and distributing high-quality Steward ferrites. Our warehouse facility has a wide range of cable and surface mount products to suit all customer requirements and all products are generally available for same day dispatch. Steward's nickel zinc ferrite parts are used extensively in the suppression of electromagnetic  interference. The Steward range of EMI ferrite that Kemtron offers includes: 

• Cable ferrites, comprising solid and split core versions for use on round and ribbon type cables. Broadband & High Frequency versions are now available for round and cylindrical cores. 

• Board Mount Products, comprising chip ferrites, common mode chokes, multi-turn devices etc, many available in both surface mount and through hole board versions.

Cable Shielding Jackets

At Kemtron we offer Kemzip cable screening products that have been designed specifically for wrapping around cables which require EMI/EMC protection. They are especially suitable for retrofitting to products already in production that are suffering from RFI radiation or conducted emission susceptibility problems. Kemzip is UV, ozone and weather resistant and is designed with self-extinguishing materials operating over a temperature range of -30°C to +105°C. Examples of some of the range include: 

• Zip-on light weight tubing especially for ribbon cables. Jacket material is laminated to aluminium foil to provide full EMI shielding. Tinned copper grounding braid is attached to inside overlap for termination.   

• Highly flexible EMI shielding and protection. Knittedwire mesh in 2-ply material with tinned copper braid attached to inside overlap provides seal and solderable termination point. 

• Light weight EMI shielding designed especially  for applications where high flexibility is required.  Basic material is PVC-GPs with Ni/Cu polyester cloth.

EMI Shielding Laminates

Kemtron offers a unique range of laminated shields in a range of materials and thicknesses that help to provide cost-effective solutions to a variety of shielding problems. Our team of high-trained and vastly experienced designers can also design bespoke laminates for individual customer requirements in order to provide a more effective solution than a standard product. Kemtron shielding laminates commonly provide a removable RFI/EMI shield in PCB housings, key board, touch panel shields and for isolating components in electronic enclosures. 

 
For more information on custom designed laminates, please contact our sales department to discuss your requirements.

Conductive Foam

Kemtron conductive foam is a low-density PET and polyurethane foam which is copper/nickel coated throughout.  This low compression sheet gasket material is suitable for die cutting or slitting for gasket applications such as I/O panels, backplanes, connectors and access panels. The material is UL94V-1flame retardant and available in 3 different thicknesses including 1.5mm, 2.3mm, and 3.4mm. Furthermore, it can roll up to 56cm wide with or without conductive transfer adhesive.

EMI Shielding Cable Glands

Our EMI cable glands are manufactured with high-quality brass and consist of 4 parts including the body, cap, locknut and the mesh olive. The cable entry gland is the perfect device for providing excellent EMP/RFI/EMI shield for screened cable which pass through enclosure walls. They are available in a range of sizes to accommodate cables with a diameter over the screen from 2mm up to 16mm. At Kemtron, we manufacture these glands as standard part though we can accommodate alternative requests such as plated finishes subject to minimum quantities. 

For more information please give us a call or visit our website.

Woven and Expanded Wire in Elastomers

Our range of EMI/RFI shielding gasket material comes in two types.  The first is woven aluminium wire/expanded Monel sheet with elastomer filler, the second is expanded Monel sheet without elastomer filler.  Both types provide a superior conductive surface, thereby ensuring low resistance contact with the mating parts.  The rubber component of the gasket provides excellent dust and moisture sealing properties.  The material is best suited to small thin gaskets, such as those required for MIL type connectors, and can be supplied on a continuous 305mm roll.  Alternatively, gaskets can be manufactured to customers’ specifications.  Visit our website for more information on our range of woven and expanded wire.

Beryllium Copper Finger Stock

Kemtron’s range of beryllium copper spring fingers and contact gaskets offer good EMI/RFI shielding, vital in applications where frequent access is required.  The fingers and gaskets can be supplied with a range of finishes, such as tin, nickel, gold and silver, to ensure galvanic compatibility.  They are heat treated to provide the right amount of spring, which is essential in closing applications where the ‘wiping’ action improves the shielding properties.  The low resistance contact fingers can be used in both high and low temperature applications and are available in a wide range of profiles and strips.  Various mounting techniques can be used to secure the fingers, including adhesive tape, machined slots, soldering or the fingers can be simply clipped on.

Connector Gaskets

All products in our extensive range of connector gaskets provide exceptional EMI/RFI shielding, with optional environmental seal.  Gaskets can be manufactured from virtually all of our flat sheet stock.  Included in our range, all of which are made from in-house tooling, are MIL types 91, 92 and 93 and ‘D’ type connectors 95 and 94.  We are happy to manufacture gaskets to your precise requirements.  Using your special designs we can manufacture custom inexpensive tooling to produce the exact gasket you need for your application.  As always, our aim is to provide you with the product you require.

Microwave Absorber

The microwave absorber material we use is supplied to us from ARC Technologies.  If you have a look at their website, www.arc-tech.com, you can see full technical details.  ARC Technologies develops microwave absorbing materials for both commercial and military applications, producing the quality and standards that are essential.  Various materials are used, including dielectric foam, gumstock, MAGRAM sheet, coated honeycomb and Ware-X.  Profiles can be extruded, sandwiched composites or polymer composite fabrication.  With this microwave absorber material, we at Kemtron can manufacture an absorber for you that will meet the most stringent electrical and environmental requirements.  Our long history of creating quality microwave absorbers will ensure that your product will meet the most demanding specifications.

Board Level Shielding Cans

We custom design and manufacture shielding cans by photo etching or pressing conductive metal.  This is then folded and soldered or tabbed to produce the final can.  You can choose from fixed or removable lids.  The can is then mounted on the PCB to provide excellent EMI shielding for one or more components.  Photo etching techniques can provide cost effective designs that can be produced quickly and supplied flat or pre-folded.  Although stamping and pressing is a more expensive process than photo etching, it does offer the advantage of high volume capability with lower unit cost for pre-folded units.  All our cans are custom designed, so please contact our sales department to discuss your requirements in detail.

EMC Solutions

We have many years of experience within the field of electromagnetic solutions and have formed close relationships with producers of materials. This has put us in a unique position in which we can offer a range of expert solutions. Our EMC solutions encompass a range of different products and services, including custom designed products, expert consultation and advice on retro-fitted components. If you would like any more information don't hesitate to visit the website. 

Electromagnetic Shielding - Environmental Sealing Solutions

We can provide advice on environmental sealing solutions and electromagnetic shielding. This can include help in designing completely new products as well as retrofitting existing components. To find out more about any of our products and services feel free to visit the website. Alternatively, you can contact our customer service team directly and they will do everything they can to help. 

Design Tools

If you visit the website you can download our helpful data sheets on a wide variety of design tools. We provide information on flammability ratings, bi-metallic corrosion, electromagnetic compatibility, handling and storage of conductive elastomers and storage and installation of Kemtron gaskets. If you have any further questions feel free to contact us directly, by phone or email. 

Environmental Sealing Materials – Elastometric Materials

Kemtron offers a wide-variety of Environmental Sealing materials solutions to suit many requirements. Our combination of vast knowledge and years of experience has enabled to remain at the forefront of providing the necessary components to maintain optimum safety within hazardous area electrical systems. Our broad selection of elastomeric materials for flexible environmental sealing ranges from silicones to polyurethane. From major plant environments to interface components of your electrical circuits, Kemtron can offer the best solution.

Environmental Sealing Materials – Flat Gaskets

Kemtron are suppliers of a wide range of flat gaskets and self-adhesive gaskets. We have the capability to manufacture many designs and styles to suit all requirements. Features and options include; Continuous lengths up to 5 metres long for slit coils, fabricated gaskets to customer's drawings, a broad range of sizes, a large selection of materials to suit multiple climatic conditions, and much more. If you would like to find out more about the high-quality and cost-effective gaskets available in this range, please visit our website or contact us.

Environmental Sealing Materials – Extrusions

For all your RFI Shielding issues, Kemtron offers a large selection of extrusion solutions. Our wealth of experience in profile design has enabled us build an extensive portfolio of extrusions to suit a wide variety of demanding applications. Furthermore, our ability to fabricate, self-adhesive back and join materials broadens the applications where extruded profiles can be used. Extruded profiles include cords, tubes, D shape, hollow D, P shape and bespoke profiles to order. Materials range from silicones to urethane foams.

Environmental Sealing Materials – Silicone 'O' Rings

Kemtron are specialists in the manufacture of bespoke "O" rings and are proud to be one of the leading suppliers in the UK. We offer a wide variety of high-quality and affordable silicone and fluorosilicone "O" rings to suit all customer's requirements. Each product is made from extruded sections cut to length and the two ends joined by vulcanisation to ensure a durable bond and maintaining the integrity of the seal. Other sections and materials that are available include sponge, hollow tube, D shape, rectangular and much more.

Environmental Sealing Materials – Form-in-Place

Kemtron Form-in-Place (FIP) Elastomer compounds are suited to applications where small, intricate gasket profiles are required. They are directly dispensed onto component hardware or enclosure via a pressurised fluid dispensing system on a numerically controlled XYZ table to form a gasket for dust and moisture sealing. Advantages of the process include; Reduced assembly time, rapid prototyping, low setup costs, smaller gasket land required, no material waste and much more. For additional information please visit our website or contact us.