Tool Calibration, A Quick Guide.


Why Tool Calibration Matters?

In the manufacturing industry, the tools and equipment on the shop floor are the backbone of the operation. The purpose of tool calibration in the Inspection Test Report (ITR) process is to continually maintain tools that require calibration. Further, ensuring the accuracy of tool calibration records plays an important role during the First Article Inspection (FAI).

The use of uncalibrated tools in the production process can delay orders or cause quality issues with your products. 

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In order to keep the shop floor running smoothly, tools must be calibrated on a certain schedule. The schedule takes into account both usage rate and that machine’s particular maintenance needs. 

The Quality Assurance (QA) department is responsible for maintaining the quality of products. Part of the quality assurance process is making sure that the tools used in the shop floor data collection and ITR are calibrated properly and functional.

To achieve this the QA department needs a practical way to keep track of all calibration records. This data should show the current calibration status and scheduled maintenance for each machine.

The calibration status states if a tool is currently calibrated. The calibration schedule includes the dates that each tool requires recalibration. A tool calibration system can maintain both these records.

Furthermore, in order to become ISO 9001 certified, you must have a tool calibration and control system in place to keep track of maintenance and predict potential breakdowns.

A tool calibration software

A Manufacturing Execution System (MES) system usually offers tool calibration as part of its platform. Although you may not need a full MES system, there are other tools to manage your calibration records.

These specialized tools can handle your calibration records and integrate them into your existing system.

Q.Shop’s solution offers a tool calibration and control module that covers all your tool calibration specifications. It contains all your inspection steps, from the First Article Inspection to your Inspection Test Reports within one unified system. If you are interested in learning more you can get in touch here.

What are tool calibration standards?

Over time, measuring equipment will slowly lose its precision due to wear and tear. 

To produce a quality product, measurement tools and equipment must be accurate. If inaccurate measurements are being collected it is costing both money and time. 

In order to know if a tool is not properly calibrated, a reference to the industry standard can be found in the NIST (National Institute of Standards and Technology). 

The NIST houses the standards that must be met in order to become ISO 9001 certified while at the same time being a reference for any measurement tool that doesn’t seem to be performing properly.

What are the different types of tool calibration standards?

There are 3 different types of calibration standards, each having a different level of accessibility and usefulness for manufactures. These levels include:

1- Primary Standards: refer to extremely high-quality measurement comparables, not useful for everyday operations. These standards are heavily math and science-based without the use of physical objects to compare to. Units are measured in terms of dimensionless physical constants rather than reference material to decide when calibration is needed.

2- Secondary or Transfer Standards: The most common reference material, aligned with NIST standards, is held by a certain company in a controlled environment to maintain the accuracy of the national standard. The instrument kept there will be what all businesses use for reference. A representative will bring the calibration standard tool to compare to your equipment.

3- Working Standards: These are certified reference materials in accordance with the NIST that are readily available for reference on the shop floor. These types of reference materials deteriorate and after a certain period are not considered traceable to the national standard. These are not always the best for your tool calibration as they may not be perfectly aligned with the standard measurement due to not being taken care of as diligently.

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How Often should you consider tool calibration?​

Tool calibration intervals are based on the usage rate of equipment but other aspects can modify the calibration schedule.

One of these aspects is the history of tool usage (how old the machine is). Another is the stability of the instrument, asking if it has had any prior issues or a tendency to breakdown. There is also the environmental factor regarding if the equipment is stored in the right place with the right temperature, humidity, and air quality.

Below is an average calibration interval chart depending on the usage, while not accounting for any of these exterior factors.

Usage RateCalibration Interval
Daily3 months
Every Second Day6 months
Once per week1 year
Once per month2 years
Once per year3 years

What are the best practices in maintaining tool calibration?

Review all your process equipment that has an aspect of measurement or product quality involved. See if it has some type of digital-analog or tracking system attached (most newer machines do).

If not, there are calibration instruments that can be added to monitor any changing aspects of the output. 

All machinery, equipment and tools used in the production or manufacturing process should have been calibrated at some point. That point should be recorded for future maintenance reference and in case of any deficiency in the final product. This way, the issue can be traced back to the specific point in production where it malfunctioned.

Simplifying Quality Inspection.

Measure, monitor, and manage quality data throughout the production cycle or repair and overhaul process. We offer production workforce management and document management solutions.