Lifting precast concrete is more and more done by vacuum handling, instead of anchors and hooks. Not surprising if you know the benefits of vacuum lifting for precast concrete products. In this article, you learn what makes vacuum handling safe and efficient. And how long it takes to reach Return Of Investment (ROI).
Let us start with the demoulding process. Due to the divided lifting force of a suction pad demoulding is possible after 8 to 10 hours. Instead of at least 24 hours with anchors and hooks. Saving an enormous amount of time!
After hours of curing, it is a shame if cracks occur during demoulding. A vacuum lifter reduces the risk of cracks tremendously. Due to horizontal demoulding and a divided lifting force.
With a vacuum, a suction pad is positioned on top of the precast concrete product and lifts the product out of the mould. Dismantling or demolition of the mould is not needed, which means the mould can is reused over and over. Saving, money time, and labour.
The suction pad of a vacuum lifter leaves the surface of a concrete product untouched. The only contact between the vacuum lifter and the concrete product is the soft rubber of the suction pad. No lifting point, no disfiguration of any kind. Leaving only a smooth concrete surface. This is different from any other lifting method.
In two seconds, attachment is done, and the same goes for detachment. Reducing the time of the complete handling cycle.
And to reduce the handling cycle even further, demoulding lifting, and turning is done in one movement. In minutes, a product is demoulded, lifted, and turned without damage.
Moreover, the complete handling cycle is done by one person, the operator. No extra manpower to install or remove lifting points or to do any other form of finishing.
Depending on the situation and customer preferences, the vacuum lifter is controlled by a manual, electric or remote control. Sucking, releasing, lifting, lowering, and turning. All easily done by pushing buttons.
Perhaps this should have been the first reason why to lift precast concrete by vacuum. The unique safety features are often decisive. Unlike any other lifting method, a vacuum lifter offers controllable safety features:
The operator can always SEE the vacuum level on a vacuum gauge. If the vacuum level drops, the operator can take corrective measures.
The vacuum lifter has an audible and visible alarm system which will go off if the vacuum level drops below 80%.
To detach a load the operator needs to push two buttons at once. This avoids accidental discharging.
If the vacuum level drops below 80%, the alarm sets in. Yet the product remains securely attached because every vacuum lifter is designed with at least an over-dimension of SF>2.
Especially for the situation of a power failure, we designed the Aerolift vacuum valve. To change the status the vacuum valve requires a positive signal. During a power failure, the valve stays locked in the same position. If suction is active, the product stays safely attached.
During the complete handling operation, no one has to be near the load. The vacuum lifter is controlled easily from inside the crane cabin or at least from a safe operating distance. Positioning, attaching, demoulding, lifting, turning, moving, and detaching, no one has to be near the load at any point of the handling process.
Concrete lifting by vacuum means no need for anchors, hooks, or lifting points. This means saving on the purchase of anchors, hooks, and lifting points. The ROI of a vacuum lifter is reached in no time. To explain, an example:
A precast concrete slab needs demoulding, lifting, and turning. This means:
4 + 2 = 6 embeds in total, which require fixing during the curing period and finally removing. Including the labour, an embed costs € 10,-.
6 x € 10,- = € 60,- are the costs to handle 1 precast concrete slab.
Every year 1.000 slabs are handled.
1.000 x € 60,- = € 60.000 is the total investment on a yearly basis. If the investment of the Aerolift vacuum lifter is € 40.000,-. The ROI is achieved within a year! And we have not even counted the time saved for earlier demoulding.
