Read the Case Study
Neighbours of a waste water pumping station in the Netherlands complained of unpleasant odours polluting the surrounding air. These were emanating from a pit, housing two large submersible pumps covered by a pair of thick hinged aluminium covers, bolted in the middle.
Despite the bolts, the covers were not airtight, so a large plastic sheet covered in sand was spread out on top of the covers in an attempt to contain the odours. Maintenance access to the pump necessitated the removal of the sand barrier, plastic sheet and the aluminium access cover with a crowbar.
The hinges were removed, and a custom-made aluminium frame installed tightly fitted into the existing one and sealed with a waterproof sealant. The frame included a removable center centre beam to accommodate two Fibrelite trench covers, and four retractable supports (two per panel) to hold the safety grids. Both the supports and center centre beam can easily be removed to create full clear access, and are secured by stainless steel fittings and cables to prevent them falling into the pit.
To contain the odour, a rubber seal was fitted to the frame and the covers secured with four stainless steel bolts to each cover. Plugs were provided for the key housings to complete the seal, and bolt heads covered.
All Fibrelite trench covers are light enough to be safely manually removed and replaced (Test Reports). This is done by one or two people using the FL7 ergonomic lifting handles, designed to ensure lifting weight stays under the HSE (UK Health and Safety Executive) advised for the distance from the body.
The finished result was flush with the top of the cover, eliminating possible trip hazards.
Innovative. Durable. Practical. Proven.
The maintenance team Ton Bertrand and Job Robben of water company Aa & Maas were very positive about the result. When they arrived for commissioning the site was completely odourless and far quieter than when the metal covers were installed, with the sound of the running water under the cover barely audible. They also showed enthusiasm at the ease of removal and replacement of the covers, and interest in rolling out onto further sites.
Piet Bus from our partner TSE in Holland said:
“Thanks to the ability of Fibrelite to produce panels that exactly met the dimensional requirements we were able to solve the problem the client was facing. Besides the perfect dimensions Fibrelite provided the panels with locking bolts at specified spots to hold the panels in place in case of over-pressure in the pit. The bolts are protected from dirt by rubber plugs.”
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