Circlip Lock Ductile Cast Iron EN124 D400 B125 Round Manhole Cover

Design Features :

The spring manhole cover is a manhole cover designed with a special spring structure, which is mainly used to enhance the stability, anti-theft and safety of the manhole cover. The core is to use the spring device to achieve a tight fixation between the manhole cover and the manhole seat to prevent bouncing, displacement or theft caused by vehicle rolling or external force impact.

The spring manhole cover effectively solves the pain points of traditional manhole covers that are easy to bounce, stolen, and noisy through mechanical locking and elastic buffering design, and is especially suitable for high-load traffic areas. The comprehensive optimization of its materials, structures and standards makes it an important safety component in modern urban infrastructure.

Structure and Principle:

**Circlip Device**: Usually composed of components such as slots, blocks, and telescopic springs. When the manhole cover is closed, the spring fits tightly with the manhole wall through the elastic force of the spring to form a mechanical lock to prevent the manhole cover from loosening or bouncing.

**Double-layer spring design**: Some products use a double-layer spring structure to further improve the pressure resistance and stability, and are suitable for high-load areas (such as motor vehicle lanes).

**Anti-bounce function**: Through the tensioning structure (such as threaded rods, nut seats, etc.) and the spring, ensure that the manhole cover remains fixed when under force, reducing vibration and noise.

Material and Performance:

**Application of Ductile Iron**: Most spring manhole covers are made of ductile iron, which has high strength, corrosion resistance and toughness. It can withstand loads of more than 80 tons (such as D400 level) and is suitable for use on urban main roads.

**Anti-slip and anti-theft**: The surface is often designed with anti-slip patterns and combined with a lock structure to prevent theft and accidental opening.

Maintenance and innovation:

**Easy maintenance**: The spring structure design simplifies the installation and removal process, making it easier for daily maintenance.

**Process improvement**: Some cities solve the loosening problem caused by aging by adjusting the spring displacement (such as 1 cm offset), significantly reducing maintenance costs.

Product Description:

Who we are

SND has been producing and selling metal goods for about 20 years.By using manufacturing techniques including sand casting, lost wax casting, lost foam casting, and precision machining, the company has been supplying goods made of materials like cast iron, steel, stainless steel, aluminum, etc. Additionally offered are surface finishing and assembly services.

Our company has successfully created products in a variety of industries, including automotive, rail transportation, agricultural machinery, chemical, energy, electricity, water, air compressor, and construction, thanks to our consistent efforts over the past few years.

Our factories' ISO9001-accredited quality control systems guarantee a consistent and dependable quality for each and every component.
Spectrometer, ultrasonic, magnetic, permeability, elongation, tensile/yield strength, and other inspections are carried out as part of routine production procedures.

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