Lifting access covers is a strenuous, high-frequency task that utility field workers need to undertake, and is a significant contributor to serious injury and lost time. With over 40,000 access covers in its service area, Icon Water went searching for a solution to help protect the safety and musculoskeletal health of its workers. However, after trialling several existing products and not finding one that met all of its needs, Icon Water undertook its own research and development, and has designed the Cracker Jack, an innovative solution to the sector-wide problem.
Lifting a heavy load
Access covers come in a range of styles and connections, and will typically weigh between 25-125kg. When they become stuck – a problem that frequently occurs – they often require loads greater than 200kg to crack, which can result in significant dynamic loads being placed on workers, and leading to long-term musculoskeletal damage.
While there are a range of methods available to crack and lift access covers, field workers will commonly do so manually using a T bar or other similar means, to help them lift the lid and drag it off of the maintenance hole.
However, this is hard work, and with some of Icon Water’s field workers lifting 20 access covers a day, they can be lifting over a ton and a half everyday.
While this is a lot of weight, field workers are used to lifting heavy loads, so in the short term it may not cause a problem.
However, the issue is with the frequency associated with lifting this amount of weight, as in the long term it will lead to musculoskeletal issues and lost time.
Eric Nielsen, Senior Mechanical Engineer at Icon Water, said Icon Water searched for a solution to protect the safety and health of its field workers, trialling a number of existing mechanical solutions, but found them to be cumbersome or slow to set up, and heavy or ineffective across the many types of terrain that workers typically encountered.
“Access covers are in people’s backyards, in garden beds, on the side of hills, they’re everywhere.
So while most solutions available are really good for flat, concrete surfaces such as in a water treatment plant or a flat road where there are no gradients, as soon as they are on grass or in a muddy environment, we found that they just didn’t suit our needs.
“This is because the ones we trialled took a significant amount of time to set up, weighed 20+ kilograms and struggled to function in the different types of terrain and scenarios our field workers often encounter.”
With no suitable alternative available on the market, and the industry as a whole struggling with the problem, Icon Water decided to invest resources into the development of a bespoke lifting device that could overcome common pain points, including being able to work on a variety of surfaces, gradients and loads, as well as being lightweight and easy to use.
Researching and developing a bespoke solution
Icon Water’s Engineering Services team took a research and development style approach to solving this problem.
This involved rapidly developing and testing concepts, through the use of Autodesk Inventor to trial different kinematic scenarios, as well as through building component/sub-assembly level prototypes as quickly as possible.
This design methodology was a departure from how design is usually delivered at the utility, which is typically completed by external resources for water assets rather than products.
This meant significant upskilling of staff was required, as well as a high level of engagement with end users right from the beginning of the project.
“Using an R&D style process, we were able to design, build, test and iterate, before going back to the start to see what worked, what didn’t and then modify the design to try it again,” Mr Nielsen said.
This process allowed us to arrive at a solution pretty rapidly, as opposed to spending a lot of time designing and not knowing if what we were doing would work.
We did a lot of designing, building and testing to prove concepts rapidly and then implement them or modify them as necessary.”
A key step in the design process was analysing the different situations and reasons behind field workers needing to lift access covers.
“We realised that around 60 to 70 per cent of the time, a lot of the field workers are lifting access covers just to inspect the inside,” Mr Nielsen said.
So they’re not actually removing the access cover to gain access and get into the maintenance hole.”
Mr Nielsen said the team decoupled the two functions of lifting and removing the cover to come up with a solution that can significantly reduce loads on the user.
In the event that the user wants to simply inspect inside the cover, they crack the access cover using the Cracker Jack and use an IP camera like a GoPro connected to a selfie stick and iPad to look inside the maintenance hole.
This takes less than a minute and requires no load from the user. When the user needs to remove the access cover for entry, they crack the cover, drop it onto a bespoke roller and then simply roll it off, which also requires little effort and minimal time from the user.
Introducing the Cracker Jack (CJ)
Weighing only 10kg, the CJ is a novel, lightweight, portable system for lifting access covers. With a working load limit of 500kg, it significantly reduces loads on the user compared to manual lifting methods.
The CJ consists of a jack driven by a battery-operated power drill, a specialised roller and wifi camera system. The jack and wifi camera allow users to quickly crack and inspect inside access covers without any load from the cover being placed on them.
When the access cover needs to be removed, the jack and specialised roller can be used to crack and remove the lid with minimal effort.
The system has been tested and proven to work with all types of access over, terrain and gradients that field workers often encounter.
Mr Nielsen said the main benefits of the CJ are that it’s easy on the musculoskeletal system, it doesn’t require a lot of force and is quick to use.
“Workers can use it to crack an access cover, and take a look into the maintenance hole in about a minute, and if the lid needs to be cracked, it can crack and roll it off within two minutes,” Mr Nielsen said.
“In that instance, you can see the major benefit between something that weighs 23kg, takes five minutes to use and takes a significant amount of effort and work on the operator’s behalf to actually employ versus the CJ, which you can set up in a minute and crack the manhole with no effort.
“In one test, the CJ was used on a steep, slippery driveway to crack and remove an 80kg circular cover in approximately one minute, which placed a peak momentary 15kg load on the user.
If this had been done manually, it would have taken less time, however there would have been significantly more load placed on the user (peak momentary load of 80kg).”
The future of the CJ
Mr Nielsen said Icon Water is continuing to trial the CJ in its operations and plans to release the design via its website, allowing other water utilities across Australia to use its innovative solution, and help improve the design and methodology for safely lifting access covers.
“We’re at the point now where we’re releasing a final prototype to the field workers to use. So we’re getting multiple Cracker Jacks made, and our field workers will continue to use it and give us feedback,” Mr Nielsen said.
“We’re also going to release the design documentation to the market and other utilities without any licensing associated with it, so other utilities can pick it up, with the aim of benefiting the backs of many.”
