Measurement takes an important key role when it comes to producing a high-quality and precise product. And calibration comes into play in a certain part of the process.
During manufacturing, everyone desires error-less production. But to get an accurate product, of course, we require certain measuring instruments to calculate the dimensions and other things. Unfortunately, what if our measuring instruments decays inside? What to do if we get an imperfect result?
The same thing goes to making tools for example. When we use the metal lathe to make tools, we require dial indicator to make sure that the roundness of the head is in good condition. The head roundness will impact the end result.
To understand whether a particular instrument decayed or not, we must calibrate them. In this article, we are going to discuss the dial indicator calibration and its process so that you could follow and apply it to your dial indicator.
What is Calibration?
Calibration is a process of documentation where the measured values compares the standard the value and find a tolerance range. In this process, a measurement device is compared to a traceable reference device.
We know that traceability is a condition where no links are missing to the real agreed reference standard. To know more about the traceability standard, please click here.
We know that dial indicators measure the relative positions on the object surface. So, while manufacturing we must check whether our dial is ready for the measurement or not. This process of checking is known as the calibration process.
Why is Calibration So Important?
Dial indicators are made of several gears and pinions. While using the dial indicator, gear meshes gear all the time. It has a mechanical life. It decays inside while meshing each other. So, we must replace them after a period of time.
Dial indicators are used in both the educational and industrial sectors. The main importance of calibration is:
- Ensures the quality of the products: To make sure our instrument works fine, we need calibration. Ensuring the tolerances in the instruments, we can make sure the quality of our products. We know if the tiny dimension has defects while manufacturing, it may cause danger while using the product. That’s why while manufacturing we must focus on the calibration.
- Ensures the quality of the study: The basic of learning grows from childhood. Students start learning what is dial indicator in this period. They have fantasies on the results and calculations they get from the lab. If their results are not satisfactory, they will lose hope. That will be the biggest mistake of a country. So, to ensure the better quality of the study, the lab teachers must calibrate their instruments in time.
Besides, there are more benefits of calibration, such as it ensures safety, it determines the replacement of the instrument, etc.
When Should We Calibrate our Dial Indicator?
Dial indicators degrade with time and use. It depends on how often we should calibrate our dial indicator. Depending on the following aspects, we can determine the calibration time.
- Industrial Uses: Normally uses of dial indicator in this sector is more often than the other. So, the calibration in this sector should be more often too. There are many companies usually calibrate their instrument once a month, some do it once a 2 month, etc. depending on how frequently the instrument is used.
- Workshop Uses: workshops don’t contain products like the industry. Normally they make tools for the household. Their usages of the instrument are less often than the industry. Therefore, normally they calibrate their instrument once a 6 month or once a year depending on how frequently they use their instrument.
- Educational Uses: In the college or University, these instruments are normally kept in the measurement laboratory. Students normally use this equipment once a week. Most of the time in a year it is not used. So, in this case, the calibration time can be less than the workshops or industries such as once a year or 2 years depending on the University programs.
Why NIST Traceability Matters
NIST or National Institute of Standards and technology is a physical science laboratory. The main task of this institute is to promote industrial competitiveness.
NIST traceability matters on the dial indicator because no other calibration certificate can be as reliable than the NIST traceability certificate. Though Mitutoyo and other renowned companies provide their traceability certificate, NIST traceability can promise us the quality and the accurate product.
Therefore, when your measuring instrument requires a NIST certificate to work for professional jobs, it’s common that you have to pay an extra amount of money for a request.
How to Calibrate A Dial Indicator at Home?
In one hand, requesting a calibration certificate is an expensive way and takes some process, but in the other hand, you must calibrate your dial indicator as soon as possible.
To ensure that the dial indicator is in good condition, you are possible to get an easy way to successfully calibrate your dial indicator. While there are some simplified ways of calibration, the most common way is the calibration using the block gauge.
In this process, we will need a gauge stand, a surface plate, and appropriately sized gauge blocks. The dial indicator is mounted on a gauge stand on the surface plate. The gauge block is placed on the surface plate.
The gauge block has its standard value according to the ANSI. However, you have to measure consecutive values from your dial indicator. And then you’ll find an average of them.
Later on, we judge our values with the standard one and find the tolerances of our dial indicator. For example, Our standard has 0.05″ of a part and our dial indicator finds 0.046″. Now we see that our dial indicator has an error of -0.004″.
You must make a document to note down the results. Let’s say you have consecutive 5 parts of measurement. You note down each of their standards. Then you make a table for each of them. After that, you take 3 consecutive values from the DI and find an average. And then we calculate our tolerance values.
Keep in mind that you have to pay attention to your document quality. You must make it more formal. By giving the date, we can track your DI degradation factor. Besides, we can get an idea when should we change the dial indicator. You can also check your DI after buying the products from the manufacturer.
Therefore, every time we measure using our dial indicator we have to adjust our values with the tolerance. This is the simplest way we can calibrate our dial indicator at home.
Calibration is not only useful for Dial Indicator but also useful to many precision instruments. To get an accurate product, we must examine our dial indicators first. After all, We have understood how important it is to calibrate the DI. And we got an idea of how often we should calibrate our dial indicator.