Municipal castings

Learn about KORUM, the D400 roadway manhole cover for periodical inspections and heavy traffic.

d 400 cover, periodic inspections, intensive traffic

Quality and conformity


  • KORUM holds NF 110 certification issued by AFNOR.
  • It benefits from the FDES Environmental and Declaration Form covering PAM roadway products, available on the INIES database and in compliance with standards NF EN ISO 14025 and NF EN 15804+A1 and the French national complement XP P01-064/CN. The FDES has been checked by an independent third party.

Product marking and personalization

KORUM can be supplied with markings (mains drainage, storm drainage, etc.) and personalization (logo of a water supply and treatment body, town crest, etc.). To ensure safety, the cover features all the validated customer markings when it leaves the foundry. There are no added, screwed, bonded or welded markings. The product is fully complete, safe and in conformity with EN 124.

Operating safety


KORUM is fully suited to periodical inspections and designed for operators who attach great importance to ensuring that the maintenance agents can work under safe, simple conditions. KORUM is designed to limit the efforts required during visual inspections and access to mains drainage systems. The most appropriate tool for removing and inserting it is a pick.

  • Handy and safe to handle thanks to the fitting
  • Easy to handle: reduced clearances and gaps, prevention of cover fouling
  • Precise, safe guiding of the cover by the fitting, during removal and insertion
  • Prevention of the risks of getting fingers caught
  • KORUM’s design ensures a very long service life: no contact between the KORUM fitting and frame once the cover is locked in place
  • Safety locking of the cover when opened at 90° to prevent any sudden or accidental closing during handling and inspections
  • Lifting rings integrated in the frame facilitate transport of KORUM and its placing on a manhole, in full safety
  • Automatic locking without any accessories: no need for keys or screws, the KORUM cover is locked in place automatically by a flexible bar when it is closed
  • The flexible bar does not require any adjustment or maintenance; it remains safe and efficient, even after many releasing and locking cycles
  • Effortless release and removal of the cover
  • The cover is released using the sharp end of a pick
  • Reduced levels of effort during handling: opened using the flat end of a pick
  • Physiological constraints significantly reduced: no need to bend over when releasing or locking the cover

Public safety

High levels of sturdiness

KORUM is a very sturdy manhole cover, designed and manufactured to stand up to the repeated stresses of heavy traffic. Tested during its design phase on the carrousel at our research centre and then on roads, KORUM showed its sturdiness, validating the constancy of its performance levels over time. KORUM is made to stand up to large numbers of cars and trucks in urban areas and on major roads, for a very long time.

Intelligent design

no risk of deformation under intense and rough traffic conditions, rigidifying rings

KORUM frame: new high-performance profile

  • Reduction of the risks of deformation in the event of rough placing or demanding traffic conditions
High strength, long service life: double rigidifying rings

KORUM covers: new design, optimized resistance

  • Prevention of all risks of deformation under heavy traffic: specially shaped ribs
Stable, safe behaviour and under heavy traffic: increased cover insertion depth in the frame

Flexible locking system: safe and reliable

Fully reliable contact between cover and ring: the permanent tension in the flexible bar locks the KORUM cover in its frame in full safety; KORUM is ready to stand up to the most demanding traffic conditions

New composite ring

  • Very high level of resistance to wear, crushing, fatigue, breakage, and any abrasion caused by sand or gravel
  • Excellent mechanical behaviour under climate constraints (temperatures)
The new composite material used for the Korum ring has been formulated and tested on the carousel during the design phase and then during road tests, to make sure that it stands up to use for a very long time


Ease of placing

Stability of its contact surface with manhole shafts

The wide circular base of the frame features bosses that are designed to enhance its bearing capacity, provide extra contact surfaces on all types of shafts and hence suit various placing conditions.

Optimization of the grouting conditions

The frame design multiplies the anchoring points to enhance strength under mechanical stresses.

  • Frame with wide grouting gaps: full integration of the frame in mortar, concrete or grouting product, installation under the usual site conditions
  • Lifting rings: extra anchoring points, enhancement of the monolithic  effect of the unit formed by the frame, its grouting and the shaft

The discontinuous base geometry and the eccentricity of the gaps limit the risks of shearing of the grouting that could occur under high levels of mechanical stresses.


Associated documents