When attempting to lift or move stuck and stubborn manholes/access covers, operatives have a large selection of tools and equipment to choose from – each with their own advantages and disadvantages. Below, we outline the various items that can be used to open stuck covers, as well as their pros and cons.
The CoverUp Key
When it comes to moving stuck and stubborn manhole and access covers, the CoverUp Key is the best tool for the job. As stated in our white paper available from our homepage:
“This solution is designed for the precise problem generally faced with stuck covers; grit, grime, and corrosion usually provide significant friction for a stuck cover over a distance of millimetres due to the design of fit between the cover and frame. Hence the repeated impact force which can be administered by the CoverUp Key will successively loosen the cover, as opposed to trying to pull it free with a single applied force.”
Put simply, our key is designed to allow users to exert extreme, upward impact force on covers. With both corrosion and deposits causing increased friction between covers and frames, repeated impact is significantly more likely to loosen the cover. A single, continuous force (generated by traditional lifting techniques) does not address the additional friction. Rather, this friction increases the resistance encountered when trying to ‘lift’ the cover. Resistance may have been increased as a result of road painting, resurfacing, etc. further securing the cover in place. Again, the upward impact force exerted by the CoverUp Key significantly increases the likelihood of breaking the seal, allowing the cover to be lifted.
Drawbacks of the CoverUp Key
The CoverUp Key is not designed to lift heavy covers and separate tools are required to lift covers following them having been ‘released’ from their frames. The CoverUp Lifter, however, can be used for this if the weight of the cover is within approved manually handling limits. Since it is height adjustable and features interchangeable tips – it offers benefits its competitors do not.
Manhole Keys
Also known as lifting keys, manhole keys are solid bars with a handle at one end and a tip (designed to be inserted into covers’ keyholes) at the other. Made of different types of metal, they are economical and require no special training to use.
Drawbacks of Manhole Keys
Though affordable and easy to use, the lifting power of these keys is limited to the force that the user can generate through manual lifting alone. If a cover is not stuck in any way and the cover mass is within manual handling limits, a cover can be successfully lifted by the appropriate number of operatives.
Users of manhole keys often suffer back injuries when they encounter a stuck or seized cover. Unable to judge the force required to break the cover seal until they encounter resistance, users can easily overexert themselves, twisting and contorting to unsafe working positions, causing injuries as a result.
Hand tools
Hammers, chisels, crowbars, pry bars and more are often used by operatives looking to move and lift stuck manholes. Reliant on brute force, leverage, downward force and vibration, operatives are not generally trained to use these tools for the express purpose of breaking manhole cover seals. Benefits are limited to the easy access of these tools and the occasional time that they will release a barely stuck cover.
Drawbacks of Hand Tools
Hand tools are unlikely to successfully loosen a cover that is more than lightly stuck. Hitting a cover with a hammer to try and loosen the grit and grime that has accumulated is likely to further embed covers. Chiselling around the edge of a cover can only remove some of the accumulated dirt and using a hammer alongside the chisel will increase the risk of injury. Injuries are also possible when crowbars or similar tools are used to try and pry a cover open as operatives will often need to use themselves as counterweights.
Ultimately, hand tools are not suited to the task of lifting stuck manholes and covers. Team this with an increased likelihood of operatives suffering an injury and it’s clear why these items should only be used for their intended purpose.
Specialised Lifting Equipment
Specialised tools using high-powered magnets, hydraulic setups, etc. are widely available. Designed to move and lift heavy access covers, these tools provide an effective solution for any company that regularly encounters heavy access covers. This may suggest that specialised lifting equipment is the best option, but this isn’t the case.
Drawbacks of Specialised Lifting Equipment
Training is always required before operatives can use it to their advantage reducing injury to themselves. Equipment can be expensive, large, heavy and cumbersome and can take a considerable amount of time to setup correctly. The additional lifting power provided by these tools results in a potentially large vertical constant force, sufficient to lift both the seized cover, and the frame with it, requiring a replacement to be installed. Sometimes, the large vertical force applied is sufficient to free the stuck cover, but it is not by design. A large, constant, upward force is the wrong kind of force to apply to a stuck cover.
To summarise, this equipment can be slow to set up, is cumbersome to transport due to its weight and size and operatives need more extensive training to use it correctly. The lifting force provided by these tools can also cause damage to the surrounding area by lifting frames and leading to wasted spend.
Efficiency is key to organisational success and specialist lifting tools score higher for efficacy than efficiency. They are capable of moving and lifting some stuck manholes, but only if operatives have received the correct training and if the lid can be unstuck relatively easily. Their effectiveness is further offset by the complexity of setting them up and their sheer size. Finally, specialised lifting equipment can be prohibitively expensive for occasional use.
Specialised lifting equipment is only efficient when the cover in question cannot be moved by other means after it has been freed, typically because the cover weighs more than can safely be lifted by one or two operatives.
Conclusion
The CoverUp Key is the only tool that has been designed to specifically address the challenge of stuck and stubborn manholes and access covers. No other tool can apply the extreme, upward impact force required to break the seal caused by years of built-up dirt and grime, corrosion, etc. The CoverUp Key is best practice that the workforce will buy into. It is the only safe, effective and efficient solution to this difficult problem.
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