Terra Firma E400 Thrubeam Range

Strength by design

Terra Firma E400 Thrubeam Range
The most advanced in-road lid on the market

Terra Firma E400 Thrubeam Covers offer strong, lightweight covers for in-road applications including high traffic freeway areas.
Terra Firma Thrubeam covers have been developed to give optimum performance and are significantly lighter than concrete and ductile options.
Produced under carefully controlled manufacturing conditions our covers are precision made to ensure the highest quality fit between lid and frame. . This means less wear and the elimination of a major cause of failure of ductile iron lids.

Thrubeam covers are produced as a singular monocoque construction giving integral strength by design.
The Terra Firma Thrubeam composite access cover is robust and will not crack, warp, chip, swell, or expand. The stiff tensile structure resists all known forces on normal working conditions experienced on underground positions. Tensile stiffness is 4-6 times that of steel or aluminium.
They are suitable for in road applications and available in AS3996: Class E400
E400 Range
AS3996 Class E400 Vehicular Composite Access Covers
DN 600mm, 760mm and 900mm
Solid Round

Our covers can be locked, sealed and made in different colours.

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Strength By Design

Available Sizes

ER60 – E400 DN600mm Cover: 28kg Frame: 13kg
ER60 - Lid & frame
ER76 – E400 DN760mm Cover: 36kg Frame: 14kg
ER76 Lid & Frame
ER90 – E400 DN900mm Cover: 46kg Frame: 15kg
ER 90 Lid & Frame

Terra Firma E400 Thrubeam Range

  • High structural performance

    Structurally and fatigue tested. Meets AS3996 E400, AASHTO and European EN 124 D400 regulations.

  • Extended working life

    Composite covers continue to perform well after 20 years in service. Will not break or spin out. The torsional resistant frames eliminate many of the usual causes of wear with traditional covers.

  • Permanent anti-slip

    Exceeds 0.60 co-efficient of friction even when wet and will retain this anti-slip value throughout its working life.

  • Secure and lockable

    Additional security may be included through a bolting system that automatically disengages when the cover is removed and reengages when replaced. High security key option is available.

  • Injury free removal

    Single person removal and replacement without risk of injury. No need for any additional lifting equipment.

  • Reduced maintenance programmes

    Longevity, ease of moving and superior performance reduces maintenance programs. Fitting a Terra Firma cover is the best ‘whole life’ choice.

  • Sealing

    100 percent watertight/sand tight with an unique self cleaning edge seal.

  • Ventable

    Covers can be vented which helps prevent the build up of explosive gases. Holes conform to ADA regulations.

  • Transparent to radio waves

    Negates the lifting of covers and helps promote better signals being transmitted.

  • Non-corrosive

    Will not corrode when in contact with other materials. Unaffected by sand, salt and all chemicals met in road environments.

  • Electrically non-conductive

    Will not conduct electricity, so stray voltage problems are negated.

  • Client design service

    Terra Firma project managed bespoke design services will use our patented technology to design alternative size and shape solutions to meet customer requirements.

Technical Specifications