It’s safe to say, as humans we have always been fascinated by the intricacies of flight.

In 1678, a French locksmith named Besnier tried to fly with wings modelled after the webbed feet of a duck. Luckily, he survived the attempt. And 300 years before that, kites were seen carrying humans in China. Luckily, we have come a long way since then…

During the last century the aerospace industry celebrated a number of milestones. From the Wright brothers achieving the first successful airplane flight in 1903, to the Vostok capsule carrying the first person into space.

But not one to rest on its laurels the industry is constantly developing new technologies, and today the prospect of potentially moving to Mars isn’t too alien a concept(!), while the emergence of new advanced materials like graphene and carbon nanotubes are helping to make airplane wings more efficient by reducing weight and fuel consumption.

Weight is hugely important when it comes to designing air and spacecraft. Lighter machines can travel faster on less fuel, and even the slightest changes can make a huge difference. Weight and balance also have a significant impact on the ability to operate aircrafts safely.

So, fasten your seatbelts as we journey into why this makes the calibration of measuring equipment highly critical…

First stop: Quality and safety

The aerospace industry is subject to strictly tight quality controls for safety, meaning high quality production is needed at every stage.

Equipment or component failures on an aircraft can cost from tens of thousands to millions of pounds, while failures in flight present another enormous risk in the loss of lives.

To guarantee the structural safety of an aircraft, every element needs to be manufactured to the highest quality. This is particularly important as the industry relies on hundreds of tiny parts to build their products using high precision processes.

Dimensional measurement plays a crucial role in ensuring that these parts, including aircraft frames and stringers, meet exacting quality standards.

Without proper, regular and well-documented instrument calibration, there is simply no way to ensure safety, quality and performance – all of which are critical to the aerospace industry.

Accuracy and precision

High value satellites are launched with the requirement that they can operate for a number of decades without maintenance or repair. This makes it incredibly important to get it right the first time. But this can only be delivered through rigorous testing and validation carried out on every single component, ensuring it can survive the extremely harsh space environment.

Measurement lies at the heart of this.

In September of 1999, after almost 10 months of travel to Mars, NASA’s $125million Mars Climate Orbiter burned and broke into pieces – purely because the wrong type of measurement unit was used during the manufacturing process. Thankfully today we have the globally recognised SI units system of measurement to avoid such incidences…

Besides checking the accuracy of metrology equipment, calibration also helps to determine the traceability of the measurement.

During calibration, equipment such as micrometers, gauges and calipers are tested against an even higher-level standard, which ensures the results the tools provide are correct, and parts can be produced to the right specs.

Calibration is not a one-time mission

Calibrations have to be carried out at regular intervals. The accuracy of all measuring devices degrades over time, and calibration processes ensure that any deviations in measurement can be corrected so the device performs consistently.  

The aerospace industry in particular has specialised accuracy and reliability specifications for its equipment, and all measurement data and results need to incite an extreme level of confidence.

This means manufacturers need to employ a metrology system that can measure equipment efficiently while consistently attaining high levels of accuracy, which can be as tight as 0.01 mm.

Regular calibration ensures that equipment maintains its stated accuracy, minimising safety risks and bringing you one giant step towards better quality.

Talk to us

Our Calibration Select laboratory in Birmingham follows strict standards and processes which enable us to carry out metrology equipment calibrations for the aerospace industry.

We offer our customers the choice of either traceable or UKAS calibrations. If you want to find out which option is right for you, or if you’d like to know more about the calibration of your metrology equipment our experts are on hand to offer some friendly advice. We’d love to hear from you!

Humans have a long, successful history of adding value to raw materials to turn them into something more useful. Prior to the advent of manufacturing, it’s daunting to think that most products were made by hand. But luckily, the technological changes brought about by the Industrial Revolution dramatically changed our ways of producing goods.

Henry Ford’s introduction of the assembly line in 1913, for instance, made moves towards efficiently mass-producing an entire automobile. His first assembly line cut the time it took to construct a car from over 12 hours to an impressive one hour and thirty-three minutes!

Today this important innovation has enabled manufacturers to create products in high volume at a remarkable rate, enabling them to take advantage of economies of scale. But manufacturing also requires balancing efficient production and effective quality control measures to create safe, high-quality products.

This is where calibration takes the load off…

Calibration and its role in manufacturing

With the ever-increasing influx of automation, it’s important to ensure that production is repeatedly accurate.

Parts need to be produced within a customer’s required specifications, within a pre-set tolerance for error, which means the highly complex machines that are involved in producing and assembling those parts – at every single step of the manufacturing process – need to be reliable.

Metrology equipment is used by manufacturers to ensure that their products and their parts are accurately and precisely manufactured, measured and assembled. The process that checks the equipment used is delivering accurate results time and time again is calibration.

Why calibrate?

To ensure that metrology equipment – from torque wrenches to micrometers – are producing the correct measurements, they need to be regularly checked.

This is important as, over a period of time and from constant use, their measurements can shift slightly, which can create differences and product deviations, beyond the famed margin of error.

Instruments used within manufacturing environments are particularly vulnerable to this. Micrometers, for instance, are widely used to assure the quality of parts, but simple changes such as heat from the hands can warm the frame of a micrometer, causing significant measurement errors. Similarly, if it’s been dropped or damaged in any way, it’s important to ensure, through calibration, that the tool is still delivering the correct measurement results.

But it’s not just quality assurance calibration offers manufacturers, it also brings a number of other important benefits:

The benefits of calibrating to manufacturers

  1. Create confidence in products – During calibration, the results from a measurement device are compared against a traceable reference device with a higher level of accuracy. Any discrepancies found can then be adjusted accordingly. By ensuring accuracy at every level of the manufacturing chain, manufacturers have confidence that their equipment is producing high quality products, which feeds down to trust from their customers.
  2. Ensure safety and quality – Having accurate measurement results is particularly important when looking at the levels of tension required within critical joints and fastenings on cars, aircraft, and heavy-duty machinery. The measurement of torque is one of the most important aspects during the manufacturing of high-quality products and is required to ensure that the fasteners used in automobiles, for example, are installed securely. The joints need to be bound with absolute tightness, which is critical to safety.  Without properly calibrated equipment, it’s impossible to meet quality requirements, such as ISO.
  3. Reduce costs and manufacturing errors – Small measurement errors can equal big costs, so having accurately calibrated equipment can reduce the risk for product defects and therefore expensive repairs.

How often should equipment be calibrated?

Dimensional equipment such as calipers, are one of the most common hand tools used within manufacturing. Due to their precision accuracy it’s important to calibrate these devices at least once a year. Similarly, torque wrenches should also be calibrated at least once a year due to their high level of use.

Other questions to consider when thinking about the frequency of calibrations are: Is the device dropped or banged constantly? Or are you using the tool in unusually hot, cold, humid or wet conditions? If yes, you might want to consider a more frequent calibration schedule.

Luckily, calibrations don’t need to be laborious …

We’re here to help

If you’re a manufacturer and you’d like some advice on calibrations within your business, reach out to our experts. We offer both ISO standard calibrations and UKAS accredited calibrations across a full range of metrology disciplines in our labs, including torque, temperature, dimensional and electrical equipment. We’d love to hear from you!

Having your electrical test equipment regularly calibrated is a crucial part of its ownership. Whether it’s a portable appliance tester, RCD tester, multifunction calibrator or an insulation and continuity tester, an annual calibration will ensure your electrical test equipment is working to the correct specifications and giving you the results you expect.

Our metrology equipment calibration expert, Tom Bates, answers your commonly asked questions about electrical test equipment calibration.

Why is it important to calibrate electrical testing equipment?

When it comes to electrical safety, using inaccurate electrical testing equipment could present a number of risks and potential legal repercussions. Even a minute discrepancy in the results could pass an item that should be failing, and vice versa – making calibrations extremely important as they ensure your device is providing accurate readings.

What can cause my electrical testing equipment to give inaccurate results?

Electrical testing equipment can be easily compromised. From an electrical surge damaging the internal components, to a moisture intrusion if the device is left in storage for a long period of time, or even accidentally dropping the device or hitting it off a hard surface – your equipment might still work after such events, but you can’t be sure that it will still give you completely accurate results.

Additionally, general wear and tear through daily use can also cause the results of your device to drift over time. The shift may be small and insignificant, but in some cases, especially if you are working with small values, it may cause a slight difference in measurement.

What happens during an electrical calibration?

An electrical calibration is the process of verifying the performance of any instrument used to test or measure electrical parameters such as voltage, current or resistance.

During an electrical calibration an accredited calibration laboratory will check your equipment to make sure it is working to the correct standards. The calibration will take place under carefully controlled and maintained conditions, using a piece of reference equipment called a multifunction  electrical tester calibrator, which is at least four times more accurate than the unit under test.

After the calibration is complete, your electrical test equipment is returned with a calibration certificate which details the test performed and the results.

Your calibration certificate is your proof that your equipment is working within standard; without it, you have no way of knowing whether the results you are generating are accurate or not.

How long does an electrical test equipment calibration take?

Using traditional manual, multiple-product methods with discrete resistors, decade boxes, and other custom solutions, the calibration process itself can take up to an hour.

However, at our Calibration Select laboratory in Birmingham we recently invested in Fluke’s new 5322A electrical tester calibrator. This innovative piece of testing equipment has made the calibration process four times faster, meaning we can complete a range of electrical calibrations in as little as 15 minutes!

Although the calibration itself is a quick process, if you’re sending your items to a laboratory for calibration, we strongly advise you check what the lab’s current turnaround time is and if they offer a guarantee if they don’t meet these timescales.

Can’t I just check my device’s reading against another device?

No! It’s a common misconception that two meters are ‘calibrated’ if they both give the same reading during a field comparison check. But this does not necessarily prove that the two meters are accurate as they could both be out of calibration by the same amount.

The only way to ensure your device’s accuracy levels is to calibrate it against a known standard.

Are there any questions we’ve not answered?

We hope that’s answered any questions you have about electrical test equipment calibration. If there’s something we’ve not covered, leave a question in the box below and Tom will get back to you.

Electrical testing equipment calibration

The accuracy of electrical testing equipment can drop over time. To avoid safety issues or process failures, it is critical to ensure that any electrical testing equipment used within your business is regularly calibrated.

There are no official British standards which state the frequency of electrical equipment calibrations. So unfortunately, there is no short answer to the question.

Every instrument will have a different calibration frequency requirement that comes recommended by the manufacturer. Combine that information with industry best practice which advises leaving no more than 12 months in between calibrations and you’ve got a good starting point.

However, there are also other scenarios where more frequent calibrations could be required:

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