Acuity Process Solutions (United States) - Are you finding yourself too often frustrated with your load cells? Are they giving you problems? Are they disrupting your process flow? It is an open secret: conventional, strain gauge load cells can be delicate and can be sensitive to even the slightest overload, side-load, or twisting force, requiring them to be recalibrated. The calibration process can be costly in terms of the equipment and training required to perform them in-house, or the expense of hiring an outside firm to perform the work. Finally one must consider the opportunity cost of having the piece of equipment out of service during the calibration.

Conventional load cells require excessive protection from normal manufacturing processes:

Because strain gauge load cells can be delicate as described above, they often require a method to protect them from these potentially-damaging forces. In order to safeguard a load cell, manufacturers may use either a complex mounting kit or some other method to isolate the cell. This is especially true when end-user operators are interacting with mobile pieces of equipment such as tanks or single-use mixers that may hold large volumes of product. During movement, the potential for bumping over thresholds, elevator transitions, or an accidental collision with a lab bench could cause strain gauge load cell calibration to be lost. To protect against this, some load cell manufacturers may require isolation of the load cell by using a physical lock-out mechanism that may even require a worker to get down on all fours.

Loss of calibration results in loss of productivity:

Manufacturers know that when traditional load cells do lose calibration, at best it will require a recalibration process. At worst, it can potentially cause a deviation in the plant’s production process that can trigger an expensive investigation to determine if a product batch was adversely affected. They must also spend valuable work hours and expense to clearly understand the root cause and create a corrective action plan.

Other Calibration expenses:

While periodic calibration is required on almost all equipment in a life-sciences facility, it is the unplanned, unexpected recalibration that can create significant impact for a client. If they do not have in-house expertise, scheduling a calibration firm to make a last-minute visit can incur expedite fees or delay the return of a piece of equipment back into service.

Even if calibration is done in house, the process can incur significant cost. Manufacturers either have to invest in the necessary equipment, NIST weights that need to be periodically recertified, or they must employ a calibrated liquid flowmeter using purified water.

Single use equipment can also incur the significant cost of the equipment liner if water calibration is employed. Because the equipment does not hold water on its own, a liner must be used to contain it during calibration and it may be disposed of after a single calibration. Not only can these liners cost hundreds of dollars (or more), but they also have an adverse impact on the environment when they are thrown away.

Even stainless steel equipment without liners can incur significant cost when water-calibrating. The high-purity WFI or USP water is very costly to make and is flushed to drain after each calibration. As an example, one of Acuity’s clients has estimated that they incur over $80,000 in annual cost for purified water order to calibrate 29 large format tanks. Imagine if there was a way to manage this expense.

Stop dealing with troublesome load cells: Acuity has the solution:

When selecting weighing technology, the obvious goal is to find a more robust weighing system that maintains calibration even when subjected to adverse force. One should also investigate innovative methods to perform calibration in the field. While no technology is perfect, Better Technology is available today.