Industrial 600mm Circular Composite Manhole Cover, 40-Ton D400 Load Class

40-Ton Composite Manhole

The Industrial Composite Manhole Cover provides a robust drainage solution designed to meet the rigorous demands of heavy-traffic infrastructure and municipal sewerage systems. This 40-ton rated circular unit utilizes advanced fiber-reinforced polymer technology to deliver a high strength-to-weight ratio compared to traditional metal alternatives. It is specifically engineered to resist the corrosive effects of sewer gases and environmental weathering while maintaining structural integrity under constant vehicle loading.

Built for the Job

Site supervisors and civil engineers select this D400 class cover for installations in carriageways, industrial estates, and fuel station forecourts. The non-conductive nature of the composite material makes it suitable for areas with underground electrical cabling or sensitive utility infrastructure. Because the material has zero scrap value, it effectively eliminates the risk of theft which is a frequent issue with cast iron components on remote job sites. The assembly maintains its shape and load-bearing capacity even in high-temperature environments, ensuring long-term safety for road users.

• Installation in main arterial roads and heavy-duty parking bays.

• Use in corrosive environments like chemical plants and sewer mains.

• Utility access for telecommunications and electrical networks.

Product Highlights

High Load Capacity

The unit is certified to EN 124 D400 standards, capable of supporting 400kN test loads.

Theft Deterrence

• Zero resale value as scrap metal compared to ductile iron.
• Integrated stainless steel locking bolts for added security.
• Reduced site liability and replacement costs.

Chemical Resistance

The SMC material resists hydrogen sulfide, sulfuric acid, and road salts without surface degradation.

Technical Specifications

What’s Included

• 1 x Circular Composite Manhole Lid

• 1 x Heavy-Duty Composite Frame

• 2 x Locking Bolt Assemblies

On-Site & Workshop Notes

• Ensure the frame is bedded in a minimum of 100mm thickness of C25/30 grade concrete for maximum stability.

• Clean the seating flange of all debris before closing the lid to prevent rocking or point-loading damage.

• The non-conductive properties of this material provide an extra layer of safety when accessing underground electrical junctions.

• Check that the locking bolts are tightened to the manufacturer’s specified torque to prevent vibration loosening in high-traffic zones.