Lifting arrangements

Wrekin provide multiple lifting provisions in cover elements:

• BS 7903 Large closed keyways for BS 7903 Large lifting key profiles
• Centrally-located cover keyways intended for horizontal (balanced) cover lift
• Perimeter keyways for ‘opposed’ cover lifting arrangements or hinged opening.

In the cases of D400 double-triangular, non-hinged cover arrangements, the cover elements are coupled together using loose-linked fasteners and so require lifting as a pair.

We always recommend that a risk assessment is carried out taking into account the combined (linked) cover weights and any possible increase in lifting-resistance from in-service changes. e.g. debris entrapment.

Such a risk assessment would determine the safest and preferred method of cover lift from a particular users perspective, including using mechanical devices and/or manual lifting key tooling, both of which would need to employ BS 7903 Large lifting-key profiles for cover compatibility.

With regards to potential cover loss (down a chamber) during lifting; it is of course possible for this to occur and it’s the reason why double-triangular covers are usually loose-linked in order to limit its likelihood.

As a further deterrent and unique to Wrekin, our standard lifting keyways also include patented safety features that deter accidental lifting-key-profile detachment during the cover lifting operation.