Vacuum lifting equipment is ideal for handling loads that must not be damaged during lifting, such as glass panels, marble worktops, and wind turbine blades. It is a versatile lifting solution, but there are several important safety considerations to keep in mind. In this article, we explain the key points.
The first step is to determine exactly what you want the vacuum lifter to do. Will you be lifting horizontally, lifting vertically, or rotating the load through 180°? Vacuum lifting equipment uses vacuum suction pads, and different types of suction pads are designed for different loads and lifting applications.
Your Vacuum Lifting Equipment Expert
Would you like to learn more about the applications of vacuum lifting equipment? The experts at Mennens are here to help.
At our locations in the Netherlands, we can inspect, certify, and proof test your vacuum lifting equipment, including testing with slightly porous loads where required. As an EKH-certified inspection company, we're happy to provide expert advice and help you select the right solution for your application.
Different Types of Suction Pads
Vacuum suction pads are available in a wide range of shapes and diameters. Their size and design determine the maximum load each pad can safely lift.
For example, a single suction pad may have a lifting capacity of 100 kg, while an array of ten suction pads may be capable of lifting 1 tonne. The number of suction pads required depends on the load. On many vacuum lifters, the suction pads can be switched on or off individually, allowing the lifting capacity to be matched to the application. The overall lifting capacity is determined by the number of suction pads in use.
An Airtight Surface Is Essential
Unlike lifting magnets, vacuum lifting equipment does not require a perfectly flat surface. Loads may be flat, curved, or irregularly shaped.
The critical requirement is that the surface must be sufficiently airtight. Vacuum lifters only work on materials that are non-porous or only slightly porous.
A Minimum Vacuum Level of 60%
The more airtight the load, the stronger the vacuum that can be achieved. Each suction pad must maintain a minimum vacuum level of 60% for safe lifting.
When the suction pads are placed on the load, the vacuum system removes air, creating the holding force. Once all suction pads have reached the required vacuum level, lifting can begin.
During periodic inspections, the minimum 60% vacuum level is always verified. If even one suction pad fails to achieve this level, the equipment does not meet Dutch inspection requirements and must be taken out of service.
It is equally important to carry out a pre-use inspection before every lifting operation to ensure the vacuum lifting equipment is in good working condition.
Visual and Audible Warning Alarms
If one or more suction pads lose vacuum during lifting, the vacuum lifter activates both an audible alarm and a visual warning signal.
This provides the operator with enough time to lower the load safely before the vacuum level becomes unsafe.
Loss of Vacuum During Lifting
Always inspect the suction pads for wear.
Worn or damaged suction pads can allow air to leak into the system, reducing the vacuum level and increasing the risk that a suction pad may detach from the load.
If the vacuum level drops below 60%, the warning alarm will activate and the load must be lowered immediately.
Lifting Slightly Porous Materials
What if the load is slightly porous, such as chequer plate (tread plate)?
With the correct precautions, slightly porous materials can still be lifted safely using vacuum lifting equipment. Normally, suction pads are selected based on the weight of the load. However, when lifting porous materials, additional considerations apply.
Using Larger Suction Pads
For slightly porous materials, suction pads with a higher lifting capacity should be selected.
Although the actual load may be relatively light, larger suction pads generate a stronger vacuum, helping to compensate for vacuum losses caused by surface porosity.
The goal is always the same: maintaining a vacuum level above the required 60% throughout the lift.
Always Test the Application
Even with larger suction pads, this approach cannot guarantee safe lifting in every situation.
For example, the porosity of the load may be greater than expected, preventing the required vacuum level from being achieved.
For this reason, the lifting method should always be tested using the actual load before it is put into operation. Your supplier can usually arrange this testing in cooperation with the manufacturer.
The Hoist Above the Vacuum Lifter
Vacuum lifting equipment offers considerable flexibility. It can be used for horizontal lifting, vertical lifting, and rotating loads.
The vacuum lifter itself does not perform the lifting. Instead, it is suspended from a hoist, which is connected to a crane or other lifting device.
Always remember that the vacuum lifter has its own weight.
For example, if the vacuum lifter weighs 200 kg and the hoist has a lifting capacity of 500 kg, the maximum load that can be lifted is 300 kg, regardless of the vacuum lifter's own maximum lifting capacity.
Reduced Capacity During Vertical Lifting
Vacuum lifters are often used to perform multiple operations, such as lifting a load horizontally, rotating it, and then lifting it vertically.
During vertical lifting, gravity introduces additional sliding forces on the load. To prevent the load from slipping from the suction pads, the permitted lifting capacity for vertical lifting is typically 50% lower than for horizontal lifting.
Do Not Leave the Vacuum Lifter Running
Once lifting operations have been completed, switch off the vacuum lifter.
The vacuum pump is driven by a motor that relies on cooling oil for lubrication. Leaving the unit running when it is not attached to a load can cause the motor to overheat, while the suction pads continue attempting to generate a vacuum without sealing against a surface.
This unnecessarily increases wear and reduces the service life of the equipment.
Knowledge file Safe Lifting
Use lifting equipment safely and correctly. Learn how to sling loads properly and how to inspect, examine, and certify lifting equipment to ensure safe and responsible lifting operations.
