The materials used for nodular cast iron well covers are high-quality nodular cast iron, coke and special spheroidizing agent from fixed-point manufacturers. The spherical grade is controlled within the range of 1 to 2, and the fine color is close to the asphalt surface layer and can expose the concrete well ring. The old gray cast iron manhole cover is gray and dark in appearance. The concrete well circle must be exposed. The color of the asphalt surface layer is inconsistent with that of the asphalt surface layer. The flatness is difficult to control and the road is difficult to integrate. It is difficult to beautify the city.

Ductile iron flat type rainwater collecting port elastic self-locking derrick cover # #; #. Applicable to ductile iron flat type rainwater collecting port elastic self-locking derrick cover: grating - 600 * 400. Support - 750 * 500 * 80 clear opening 600 * 350 * 700mm;

　　2。 The raw material used shall be nodular cast iron, with self-locking performance, to achieve anti-theft, anti rebound, anti vibration, anti displacement and impact force of bearing impact hairpin. The tensile strength shall be greater than 500-1100N/mm, and the elongation shall be 2-15%. In addition, QT500-7/European standard GGG40-50 shall also be used;

　　3。 The bearing capacity shall be ≥ 250kN;

　　4。 The clearance between manhole cover and support is 4mm ≤ a ≤ 10mm;

　　5。 The width of well supported surface shall be ≥ 20mm;

　　6。 The embedded depth of manhole cover shall not be less than 40mm;

　　7。 The manhole cover surface shall have a height of no less than 3mm # ## 8; Beautiful: simple lines, surface treatment according to needs, modern concept.

9. Anti theft design: anti-theft, safe, special opening hook, easy to open.

　　10。 High strength: The strength and toughness are much higher than that of cast iron, which can be used for docks, airports and other large span and heavy loads.

11. Specifications: meet various requirements of different environments: load, span and shape, and can be manufactured according to the size and shape provided by customers.

Application of ductile iron manhole cover:

Why do I choose ductile iron manhole cover? Ductile iron manhole covers can meet the requirements of high-grade residential roads and marble granite pavement. All products can open the plate cover, which can be used in water supply and drainage wells, ventilation wells, cable wells, instrument wells, etc. It consists of a derrick and a manhole cover. At the same time, its strength and toughness are much higher than that of cast iron. It can also be used in large span and heavy load environments, such as docks and airports. It consists of a derrick and a manhole cover, which is designed as a square groove. The profile can also be inverted trapezoid, which can make the matching between the manhole cover and the derrick more closely, and improve the existing manhole cover. The invisible manhole cover only exposes four sides of the frame on the ground. The middle of the manhole cover is sunken to a certain depth, and the bottom of the concave is designed as a curved concave with ribs. The light color concealed manhole cover is made of steel plate, and the surface can be directly paved with floor tiles.