D400 Extra large manhole covers


This unique design by Wrekin is the ideal solution when a very large access cover for D400 Group 4 is required.

Designed and manufactured to meet the enhanced requirements of Highways England’s CD534 (Formerly HA 104/09) specification and BS EN 124:2015, the Hercules™ access cover includes additional market-leading features designed to provide both greater operator safety and operational longevity.

The double triangular covers are indexed to ensure correct orientation when fitting. The cover’s M16 blank bolt can be replaced with a threaded lifting eye for mechanical lifting – the position of the bolt is at centre of mass, allowing safe and level lifts.

The covers feature a small window allowing for easy and safe inspection without the need to remove the entire cover.

Note: Additional M16 lifting points are present on Hercules cover sizes exceeding 1200×1200 Clear Opening in lieu of BS7903 Lifting Keyways, for alternative methods of mechanical cover lift.

Wrekin product code Clear opening
(C x D mm)
Base opening
(F x G mm)
Overall frame
(A x B mm)
Frame depth
(E mm)
DMT0D6/1212/4 1200 x 1200 1230 x 1230 1385 x 1385 150
DMT0D6/1515/2 1500 x 1500 1530 x 1530 1685 x 1685 150
DMT0D6/1818/2 1800 x 1800 1835 x 1835 1990 x 1990 150
  • Key features:

    D400 For use in a Group 4 Class D400 carriageway environment
    Fully compliant with BS EN 124:2015*
    Complies with DMRB (Design Manual for Road & Bridges, CD534)
    Complies with MCHW (Manual for Contract Highway Works, Series 500)
    HA104-09 Exceeds Highway England’s HA 104/09 requirements*
    support symbol Cover support geometry reduces movement relative to the frame
    indexed covers Indexed covers ensure correct fitting
    enlarged flange Enlarged frame corners help to dissipate the load
    ant-flex beam Antiflex cover – reduces cover wear
    non-rock Non rock – three point suspension for non rock stability
    keyway Safety keyway – ensures key’s secure in keyway when lifting*
    ductile iron Manufactured from strong and highly durable ductile iron
    Mechanical lifting points
    Insepection window allowing safe and easy visibility into chamber
    60+PSRV tested at top surface of chequer by UKAS accredited 3rd party
    Balanced and safe mechanical lifting with M16 threaded eye bolt

    *BS EN124 and HA 104 apply to products with a clear opening up to 1 metre. The Hercules range of access covers have a clear opening greater than this, however load capability and design features exceed the requirements of these documents.

    Please note that Hercules 1200 cover is the only cover in the range to have keyholes for manual lifting.

  • Data sheet:

    Access Covers D400 Hercules Range Sheet

    1.64 MB | Version 15 | PDF format



    Hercules™ Lifting Guide

    1.7 MB | Version V2 | PDF format