The Composite Manhole cover is made with materials consisting of 2 or more dissimilar components. These dissimilar components are usually classed as the matrix and the reinforcements. The material can be plastic or polymer, metal or ceramic and the reinforcements are either a particulate or fiber based. When the composites are fiber-reinforced then it’s called FRP and that fiber could be glass, Carbon, Aramid etc. If the reinforcing fiber is glass then the composite is referred to as glass reinforced plastic (GRP).
The traditional Manhole cover is made out of Cast Iron which has been used for manhole covers and frames since the mid-20th Century due to its durability and high compressive strength. The iron is melted and then poured, or cast, into a mold and can weigh as much as 135 kg.
Cast Iron Manholes Cover lids are being stolen these days. Stealing the cast iron manhole covers for scrap is a lucrative business for thieves allowing vehicles, people or animals to drop in the hole and get injured while the designated authority is responsible for their medical charges. Composite manhole Covers have zero scrap value and eliminate manhole lid theft making it very reliable for a very long term.
Cast Iron Manhole Cover is normally weigh between 70 to 300+ kilograms. Composite manhole covers weight is made lesser by 63% to 85% than cast iron and reduce worker Injuries.
Cast Iron Manhole Covers pop off and become a big liability for utilities and for departments who maintain the manhole. Sewer backups, storms, flooding, vandals and even truck tires can cause the lids to be knocked out of place. Composite Manhole Covers stay where they should be and locked into place.
Cast Iron Manhole Cover is made up of same composition for every design and every type of usage as a result high loads may not be bearable for some manhole covers and low weight load are used unnecessary with manhole cover based on a same level of composition. Composite Manhole Covers are available in fully traffic rated versions that offer 30% more weight loading than the cast iron.
Cast Iron Manhole Cover will have spills and will not contain extra water flow from sewages and treatment plant. Composite Manhole covers can reduce Inflow & Infiltration in sewers. The manhole covers with frames and O-ring seals help to reduce energy used for pumping excess water from lift stations and pump stations. Composite Manhole cover and frames also reduce to keep excess water, spills, and runoff out of our sewers and storm water systems and more oil and contaminants out of sewers, storm water systems, creeks, rivers, lakes, and oceans.
Cast Iron Manhole Cover for Sewer and wastewater systems can be highly corrosive. Hydrogen sulfide gas is commonly found in these systems. It is corrosive, very poisonous, heavier than air, flammable and even explosive. When dissolved in water, it becomes a weak acid called hydro sulfuric acid or sulfhydryl acid. Composite Manhole Covers are ideal for corrosive environments.
Collection systems and sewers are widely known to have problems with Hydrogen Sulfide (H2S) and other sewer gas odors. The typical foul rotten egg smell is an indicator of Hydrogen sulfide (H2S), a colorless gas is found in sewer systems. Composite Manhole lids can reduce odors.
Many Telco and electrical utility manhole applications require manhole lids and rings to be non-conductive. Composite manhole lids are well suited for these non-conductive manhole requirements. Manholes can also be fabricated and fitted with non-conductive fiberglass ladders, platforms, and railings. Composite Manhole Covers are ideal for non-conductive applications.
Cast Iron Manhole Cover don’t allow transmition of radio signals and mobile phone to pass through so it makes hard for workers in sewer to communicate due to the interruption. Composite Manhole Covers allow AMR and radio signals to pass through easily.
Utilities are facing ever increasing operating costs. Higher fuel costs combined with higher vehicle acquisition and maintenance costs have managers looking for more creative ways to save the budget. Composite Manhole Covers Reduce Operation Costs and Save Energy.