Load cells: load discrepancy, fault slip and Irish cream!
How much does an MRI weigh?
Following on from our last article on correct load weights, Project Cargo Global reported how a Dutch lifting and rigging company discovered a 5 tonne discrepancy between the declared weight of an MRI machine, and the actual weight. By using compression load cells to weight the cargo before unloading, they were able to lift it safely using the correct rig.
As explained in our last article, the weight and the centre of gravity of a load may not be accurate if the weight is not evenly proportioned. As the company representative said;
“Jacking timbers were used to raise the scanner so the load cells could be positioned. The load cells were positioned and then a connection to the laptop was made. Upon configuration, the trailer was lowered to let the (MRI) unit rest on the load cells.”
Or a canal bridge?
The same principal was used to weigh a repaired canal bridge in Brussels which had been damaged in a collision with a vessel. According to the Cranesy website, load cells were used:
“To provide measurements before and after an important phase of the bridge’s restoration. The wireless load cells were positioned under four supporting points of the structure and fed data, capturing individual and collective readings, back to … software on a laptop, where they were read at a safe distance.”
Fault slip stabilisation
Now this is not normally an issue, but with the rising interest in fracking in the UK, it has more relevance than before. A team of researchers set out to discover if the models they created in the lab were consistent with results in the real world.
The issue
Geological faults can slip seismically, potentially causing an earthquake, or aseismically. Fluid injection into a natural fault can induce fault slip. Initially the fluid speeds up the opening of the fault, and then can actually promote stable fault creep as the pressure rises. Seismic activity, the team concludes:
“Is most probably triggered indirectly by the fluid injection due to loading of nonpressurized fault patches by aseismic creep.”
The tests
The team used load cells in the lab setting to conduct their fluid injection experiments as follows:
“We (used) a biaxial apparatus (BRAVA) configured in a double direct shear (DDS) configuration within a pressure vessel to allow a true triaxial stress field. Normal and shear stress were applied via fast-acting hydraulic servo-controlled rams. Applied loads were measured internally to the pressure vessel via strain-gauged hollowed load cells (LEANE International model CCDG-0.1-100-SPEC) positioned at the ram nose.”
Efficient Irish cream production
Yes, load cells are busy in Ireland, improving the efficiency of the production of around 1.2million cases of the Irish cream every year by manufacturers First Ireland Spirits. According to the company, quoted in The Manufacturer magazine:
“We added load cells onto tanks to measure weights, automated valves to control the flow of liquid and a number of mass flow meters. The SCADA system is measuring everything, recording and logging all the batches, making the process quicker and totally consistent. The new system, coupled with the expertise of our liquid processing team, has enabled us to operate much more efficiently and has allowed us to increase plant output significantly.”
If you do follow the link, take a couple of minutes to check out the ‘cheese into vodka’ story at the top of the article. It’s got absolutely nothing to do with load cells, but it’s an amazing story of recycling and reuse where literally nothing is wasted, not even the byproduct water. You’ll never look at cheese the same whey again (couldn’t resist that one!).
Cheesed off with your current load cell supplier?
Come to us direct! We design, manufacture and ship high quality load cells within the UK with rapid turnaround times. So you’ll never be kept waiting for your load cells due to delays on the high seas or at congested ferry ports. Call us with your requirements.
