General Installation Instructions for Manhole Covers

Which general points must be observed before, during and after the installation of manhole covers? You will find suitable answers in the installation instructions listed below.

Instructions before the Installation
Magnifying glass
Check parts

Check all parts for perfect condition. Damaged parts must not be installed!


Use suitable lifting gear for loading and offloading, and for transporting parts on site.

Opening bar

Use appropriate tools for lifting out and/or inserting covers to avoid damage


Clean the contact surfaces and - if present - check the seal for cleanliness and correct fit and the closing device for perfect condition and operability before inserting the covers. Clean and moisten the underside of the frame before installation.

Instructions during Installation
Manhole cone with manhole cover
Frame Position

The frame must always be in full contact with the mortar bed and capable of bearing. If the substructure is not executed correctly, subsequent traffic load will cause loosening, premature wear, rattling, or even destruction of the cover.

Manhole cone with mortar

Prepare the mortar bed (min. MG III, DIN 1053), install the frame with full contact and align at the correct height. When installing thin-walled frames which are not torsion-free make sure the cover is fitted when installing the frame.

Manhole cone with manhole cover anchor bolts
Anchor Screws

If necessary, install anchor bolts in the shaft (e.g. pressure tight covers).

Manhole concrete ring
Height Adjustment

When adjusting the height of the manhole cover > 20 mm, concrete support rings, levelling segments or plastic-modified, non-shrinking, fast-hardening grouting mortars are recommended. For subsequent height adjustments, a new, full-surface mortar bed must always be produced.

Manhole with dirt catcher
Dirt Catchers

Insert dirt catchers.

cleaning manhole cover

Clean the top of the frame before inserting the cover and clean the contact surface of the cover.

Manhole cover insert cover
Insert Cover

Insert the cover and check for noise-free seating.

Manhole cover with screws
Secure the Cover

The screws for screwed covers are tightened as follows:

M16 with max. 100 Nm
M18/M20 with max. 120 Nm

Instructions after Installation (Operation/Maintenance)
Lifting hook for manhole cover
Opening Bar/Key

Lift out and insert the cover only with a suitable opening bar/key.

Gases escaping from the manhole
Ventilation opening time

Wait for ventilation opening time after opening if necessary (approx. 15 min.). Danger from gases!

Manhole cover removing seal

Replace seal if damaged.

cleaning manhole cover

The supporting surfaces must be cleaned before each closing.

Installation instructions for self-levelling manhole covers

Operating and maintenance instructions can be found in our download area

Information about our manhole covers

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