Presspahn Logo
NOMEX®
 

Whenever there's a need for electrical insulation, there's usually a product of NOMEX meta-aramid to fill it. In its various forms - primarily papers and pressboards - NOMEX products have the right balance of properties for use in transformers, motors, generators and other electrical equipment. This unique balance of properties has been providing reliability to manufacturers for over 25 years.

NOMEX is a synthetic aromatic polyamide polymer that provides high levels of electrical, chemical and mechanical integrity, when converted in to its various sheet forms. Used properly, NOMEX products can extend the life of electrical equipment, reduce premature failures and repairs and act as safeguard in unforeseen electrical stress situations.
 
NOMEX products have characteristics which make them ideally suited for electrical insulation applications. These characteristics may vary slightly in the different forms and types of NOMEX. The following provides a comprehensive look at NOMEX and explains the advantages of specifying it in a broad range of electrical applications.
 
Inherent dielectric strength   In densified form, NOMEX meta-aramid products withstand short term electrical stresses of
    18 to 40 kV/mm (450-1000V/mill) depending on product type and thickness, with no need for further treatment with varnishes or resins.
     
Mechanical toughness   Densified NOMEX products are strong, resilient and (in the thinner grades) flexible, with
    good resistance to tearing and abrasion.
     
Thermal stability   Temperatures up to 200°C (290°F) have little or no effect on the electrical properties of
    NOMEX products and useful values are retained at considerably higher temperatures. Furthermore these useful properties are maintained for at least 10 years of continuous exposure at 200°C (430°F).
     
Chemical compatibility   NOMEX is essentially unaffected by most solvents and is unusually resistant to attack by
    acids and alkalies. It is compatible with all classes of varnishes and adhesives, transformer fluids, lubricating oils and refrigerants. Since NOMEX products are not digestible, they are not attacked by insects, fungi or molds.
     
Cryogenic Capabilities   NOMEX has found acceptance in a variety of cryogenic applications due to its unique
    polymeric structure. At the boiling point of nitrogen (77°K), NOMEX Type 410 paper as well as Type 993 and Type 994 pressboard have tensile strengths in excess of room temperature values.
     
Moisture insensitivity   In equilibrium at 95 % relative humidity, densified NOMEX papers and pressboards maintain
    90% of their bone-dry dielectric strength while many mechanical properties are actually improved.
     
Radiation resistant   NOMEX is essentially unaffected by 800 megarads of ionizing radiation (which causes
    polyester laminates to crumble) and still retains useful mechanical and electrical properties after eight times this exposure.
     
Non-toxic/flame resistant   NOMEX products will not produce any known toxic reactions in humans or animals.
    NOMEX products do not melt and with a Limiting Oxygen Index (LOI) at 220°C (430 °F) above 21 (the critical value for combustion in normal air), they do not support combustion even at the highest operating temperatures. NOMEX products are available which meet UL94V-0 requirements.

 

Datasheets
 
NOMEX aramid paper Type 410 Page1, Page2, Page3, Page4, Page5, Page6, Page7
   
   

 

 

 


Presspahn Ltd, Wharncliffe Works, Harrogate Road, Bradford, BD2 3TB
Tel: +44 (0) 1274 636333 Fax: +44 (0) 1274 626024
E:Mail:Sales@Presspahn.com