GUEST COLUMN | THE CALDWELL GROUP
CAN I USE A VACUUM LIFTER?
It is rarely a definitive ‘yes’ or ‘no’ answer to the question because it isn’t always clear of the porosity of the load. By Bill Gridley, technical sales representative at The Caldwell Group.
ferrous material that doesn’t work with magnets. We looked at two main types of hook-suspended vacuum lifter: Powered and Mechanical. There are notable differences from a
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manufacturing perspective; we ‘add’ a power pack at the end of the process to make it a powered vacuum. The frame below the power pack is sized for the material and then the pack gets ‘plugged’ into the top, which includes the lifting eye. Regardless of the type of vacuum lifter, it is a misconception that vacuum lifters are ergonomic tools — they’re not. It is a product range that is often misunderstood because it’s true they
n an earlier instalment of this column, we looked at vacuum lifting equipment, and its ability to offer end users damage-free handling of thin or non-
are commonly found in use with jib or workstation cranes, but that doesn’t make them an ergonomic tool per se. They can weigh hundreds or even thousands of pounds and are also found below-the-hook of large overhead bridge cranes and hoists. One might even see them used with forklift trucks. Users can carry mechanical lifters around by forklift, for example, without worrying about ancillary power equipment getting in the way. As with all material handling equipment,
rather than getting sidetracked by peripheral information, it’s best to start with the application. When we’re in a conversation with a supply chain partner or end user, even if they’ve asked for a vacuum lifter, we redirect the discussion to the application itself. Based on the load, its weight, dimensions, material, etc. a picture
will emerge as to which page of our catalogue we should be turning to — if at all. The complexity with vacuum lifters is that it is rarely a definitive ‘yes’ or ‘no’ situation, because it isn’t always clear of the porosity of the load. A definitive ‘no’ would be when the load is very porous; ie, liquid or air can pass through small holes in the product such as wood and cardboard. A definitive ‘yes’ would be when the load is non-porous, such as a metal sheet or glass. However, there are many types of plastics where it is unknown at first glance if a vacuum solution would work safely or not. There are various scientific methods used to examine porosity; here at Caldwell, we conduct a vacuum test on a sample of the product that has been sent to us. Remember, mechanical vacuum lifters
are not fail-proof. Many people will debate that an electric powered unit is safer because you have confidence in that the pump is always running. But it’s the product being lifted that makes any vacuum lifter efficient. The more porous the material, the harder a vacuum lifter needs to work. Once all things are considered, the
This Caldwell Model D vacuum lifter is in use at a FASS Diesel Fuel Systems fabrication shop in Marthasville, Missouri.
conversation can continue as to which vacuum solution would be desirable. The breadth of end-use application means we can’t typically point to a specific model. We have an application evaluation sheet — and it’s a good idea to ask your suppliers for this — which seeks to garner enough information to generate a quote. But this exercise often leads our engineers to customise a solution, even if it is closely based on a pre-engineered item. There are further misconceptions over price that is considered a sticky subject by many manufacturers. Mechanical and powered components are largely the same, but the mechanical version uses physics — the up/down motion of a hoist — to create a vacuum chamber, whereas the powered hook-mounted version has the power pack described. Vacuum lifters are not new but there is scope to understand them better. That starts by knowing as much as possible about the application, the load, and its porosity.
20 | February 2025 |
www.hoistmagazine.com
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