LSZH Cross linked

Family: Elastomeric

Use: Insulation and Sheathing on LSZH cables

General characteristics

The relatively modern development in cables has seen the requirement for fire performance become increasingly important. This has seen requirements for low smoke emission, low corrosivity when burnt, flame retardance and reduced propagation become clearly specified and increasingly specified in many areas of cable installation. This has removed halogenated compounds from many markets to be replaced by LSZH – low smoke, zero halogen – types. This has dramatically reduced the amounts of PVC and chlorinated rubbers used to be replaced by newly developed LSZH materials.

The elastomeric versions of these compounds are generally based on non-chlorinated polymers of some sort with relatively high loadings of active fillers, the commonest being hydrated alumina. Compounding technology can be quite complicated depending on the application. Many compounds use EVA as the base polymer. EVA is a copolymer of ethylene and vinyl acetate, with VA contents being from single-figure percentages to 70% and 80%. The lower percentages are essentially modified polyethylene, and as the VA content increases, so does the softness, and the resistance to fluids improves. Other copolymers are often blended with EVA, including acrylics and nitriles. 

Processing

Elastomeric LSZH is compounded with carefully selected fillers, colouring pigments and processing aids using standard compounding practice. Cross-linking may be chemical or radiation. 

Extrusion is usually with single screw extruders, crosslinking being by CV, autoclave or radiation means.

Good process control is necessary to succeed with these materials.

Uses of material/Cable types

Crosslinked LSZH materials are usually used in applications where older chlorinated rubbers would have been used, as well as an increasing number of new applications where fire performance is required in conjunction with requirements for heat and fluid resistance.

Standards

  • IEC 60092 – series
  • IEC 60245 – series
  • IEC 60502-1 and IEC 60502-2
  • BS EN 50382
  • BS EN 50506
  • BS EN 50525 – series
  • BS 6883
  • BS 7655
  • BS7917
  • Def Stan 02-526
  • Def Stan 02-527

List of Polymeric materials for cables used:

Contact us

Please, don’t hesitate to contact us for additional information on our company or our products.

Other News

Our website uses cookies and thereby collects information about your visit to improve our website (by analyzing), show you Social Media content and relevant advertisements. Please see our cookies page for further details or agree by clicking the 'Accept' button.

Cookie settings

Below you can choose which kind of cookies you allow on this website. Click on the "Save cookie settings" button to apply your choice.

FunctionalOur website uses functional cookies. These cookies are necessary to let our website work.

AnalyticalOur website uses analytical cookies to make it possible to analyze our website and optimize for the purpose of a.o. the usability.

Social mediaOur website places social media cookies to show you 3rd party content like YouTube and FaceBook. These cookies may track your personal data.

AdvertisingOur website places advertising cookies to show you 3rd party advertisements based on your interests. These cookies may track your personal data.

OtherOur website places 3rd party cookies from other 3rd party services which aren't Analytical, Social media or Advertising.