Precision is a pillar of modern manufacturing, engineering, and scientific work.
Whether you’re tightening two components together or taking a reading of pressure, temperature, force, electrical output, or other critical variables, you simply have to trust in your instruments and equipment to give you a good result. But, of course, over time, anything that needs to be precise can become a little degraded, which is why tool calibration is an important factor in maintaining the high quality and standards we require from our work.
Why Is Calibration Important?
A common question from companies looking to invest in measurement equipment is: Why is calibration important, let alone needed annually, when it is still working? The difference is one of expected functionality vs proven operation.
For example, an instrument may still be working but will still be drifting out of its tolerance, meaning the measurements are slowly getting less reliable. These unreliable measurements have an impact on decision-making, quality, safety, and current compliance. Calibration is the way to identify reliable readings and prove that the equipment is performing in relation to the defined standard (reference) to ensure that this doesn’t happen.
For industries running large operations, this can also help reduce unnecessary rework and increase trust in the data used to make decisions and track manufacturing production data.
What Happens During Calibration?
Calibration is the act of comparing a measuring instrument’s accuracy to a known, correct standard. Depending on the equipment and the application, this may require one or several measurement checks over an instrument’s operating range.
The verification will determine if the instrument can perform within tolerance. If not, the device usually can be recalibrated before it’s put back into service. Record-keeping for these checks will also help an organization better know its equipment’s history.
A calibration certificate lists relevant information about the process. Equipment validated, measurements checked, standards met, calibration check date, etc. Good record-keeping can save an organization time during audits and quality checks.
The Value of Traceability
For organizations where measurement accuracy has implications in terms of regulations or contracts, traceable calibration becomes even more critical. This means that the results of a given calibration can be shown to be part of a chain of comparisons that ends with a reference to the recognised measurement standard.
This is useful not only because it gives greater confidence that an appropriate measurement standard has been used in the direction, but it can also be used to demonstrate that the organization is managing its measuring equipment to its customers, or to auditors, or other stakeholders.
When Accredited Calibration Makes Sense
Some specialized applications require a higher level of assurance than can be provided by an organization operating on its own. Accredited calibration is calibration performed by an organization that is certified to a standard for its competence in conducting specific calibration activities.
When selecting a calibration laboratory, consider the laboratory’s technical capability, the appropriateness of the laboratory’s accreditation, and its measurement capability and ranges, i.e., the type of equipment that can be calibrated, and by what degree of accuracy and precision.
Making Calibration Part of Operations
It will be most effective if the tool calibration is not an administrative task that is done from time to time, but an integral part of operations. You need to schedule the calibration based on the use of the equipment, the manufacturer’s recommendation, previous out-of-tolerance readings, risk, and any quality or operational requirements.
Planned tool calibrations, coupled with appropriate documentation, will, in combination with traceable measurement performance, instill confidence in your system. Through controlling your measurements using the techniques described above, your team members will be able to provide judgement on the data they can rely on.
