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port used heavy duty manhole cover


Quick details

· Shape: Round

· Material: Ductile Iron GJS500-7

· Duty Class: EN124 D400

· Frame Style: Bottom Flange

· Gasket Material: Neoprene

· Lock Material: SS304

· Coating: Black Bitumen

· Standard: EN124-2015

· Surface Pattern:Customized

· Surface text:Customized

Quality Control Process


Raw Material Inspection

● Raw Material inspection including chemical

● components analysis, tensile strength test and etc. 

Quality Control Groups

● Dimensions Test

● Manufacture process Inspection

● Process Inspection including sand cleaning, assembling, packing and coating

● Final Inspection including delivery marks and etc.

● Particular Tests for different products, such as Load Test, Hydro Test and etc. 


● Chemical Components

● Microstructure Test

● Tensile Strength


1.Why are most manhole covers round?

Manhole covers are round because a round cover cannot fall through its circular opening. The manhole cover rests on the frame seat; therefore, the diameter of the frame opening is smaller than the manhole cover. Whereas a square or rectangular manhole cover may fall through an opening if turned diagonally in the hole. It is also easier to dig a circular hole. Round covers are easier to machine on a lathe. A round manhole cover can be rolled, which makes it easier to move if needed.

2.Why ductile iron?

Spheroid Graphite' or 'Ductile Iron' is a unique form of Iron. which prior to the metal casting process receives crucial mineral additives to produce an exceptionally strong resistance and durable metal, the molecular structure of 'Ductile Iron' gives rise to excellent additional strength and shock load resistance, within structure carbon steel, without steel inheriting corrosion. In today's roads, Covers & Gratings are required to carry increasingly heavy and fast moving traffic, yet the need to keep the roads in service, places free from accidents and theft, additional demands on those Covers and Gratings in terms of speed and ease of access for maintenance of services is essential. 'Ductile Iron' Manhole Covers, Gratings and Frames are fast replacing the conventional 'Grey Iron Manhole Covers, Gratings and Frames on account of uniqueness in its Strength to Weight ratio, Design, Weight and the Cost benefit.

We supply port used heavy duty manhole cover.

We devoted ourselves to casting industry for many years,has been exporting to Europe and Australia since 2001. 

We are expecting become your long team partner, OEM & OED is welcomed.


Ductile manhole cover


Ductile iron GGG50/7, gray iron






Round, square, rectangle


200mm-1000mm or as per customers’ drawing


Bituminous black




Drawing-mould making-raw casting-sand blasting-rough machining-surface treatment-product inspection

Advanced technology and equipments

Tensile strength: 500Mpa Yield stress: 320Mpa


Elongation rate: 7%


Hardness: HBS170-230

Load capacity

B1125 C250D400 E600 F900


Machining:+/-0.02mm, finish machining:0.002mm


Footway, pedestrians, car parks, aircraft pavements


Longevity corrosion resistance, excellent anti-pressure