Regularly checking and calibrating industrial-grade torque tools is an essential part of quality control for any production line, and vital to maintaining a productive line, high-quality products, and worker safety.
Torque tools need calibration to ensure that they are functioning properly, complying with international regulations and standards, and producing repeatable, accurate results. 
This is not a one-time event, but rather an ongoing process with a set cadence; a maintenance & calibration schedule should be part of every company’s quality control process.
Any time a tool is found to be inaccurate, it can be adjusted or repaired as necessary to restore its precision for its intended application. A maintenance schedule can also help identify potential issues before they become major problems, allowing for more efficient and effective maintenance and repairs.

The frequency at which torque electric screwdrivers should be calibrated depends on several factors, including the type of screwdriver, its torque range, its frequency of use, and the level of precision and repeatability required for the application.

However, at a minimum you should calibrate any torque electric screwdriver at least once a year.

Certifications and standards

ISO (International Organization for Standardization) and NIST (National Institute of Standards and Technology) certification for torque electric screwdrivers may be required in certain situations where high accuracy and traceability are critical.
For example, ISO certification may be required for companies that operate in highly regulated industries, such as aerospace, automotive, and medical devices, to demonstrate that a company has established a robust quality management system and that their equipment is calibrated and maintained to a high standard.
NIST certification, on the other hand, is a voluntary certification program offered by the National Institute of Standards and Technology in the United States. NIST provides traceability to the International System of Units (SI) for a range of measurement equipment, including torque tools. Certification to NIST standards can demonstrate that a company has established a traceable calibration system and can provide documented evidence of the accuracy of their equipment.
In general, ISO and NIST certification for torque electric screwdrivers may be required in situations where the accuracy of the tool is critical to the product quality, worker safety, or regulatory compliance. However, the specific requirements for certification will depend on the industry, the application, and any regulatory requirements. It's important to consult with a qualified calibration service provider to determine the appropriate certification and calibration requirements for your torque electric screwdrivers.

Where and how to calibrate your torque tools

As far as conducting the actual calibration, companies have two main options:

• In-house calibration

If you choose to perform your tool calibration in-house, you will need special calibration equipment and trained personnel but it can be a quick and cost-effective option.
This is most appropriate for clutch tools, as precision is less important.

Here’s our recommendations for each family of Kolver electric screwdrivers.

As far as Kolver’s clutch-based electric screwdrivers FAB, RAF and KBL go, we recommend calibrating them when first setting up the tools for your production line and then anytime the ramp and speed settings are modified, and every 500,000 cycles; but at least once a year.

We recommend using Kolver’s Mini K/S torque analyzer as illustrated in the following videos:

FAB & RAF Series calibration

KBL Series calibration

When it comes to our PLUTO, MITO and NATO current-controlled electric screwdrivers, in-house calibration is also first done at initial setup and then again every 500,000 cycles or once a year. 

A step-by-step PLUTO/MITO/NATO calibration tutorial, using one of Kolver’s torque testers, is available at the following link:



It’s a bit of a different story when it comes to transducerized tools like Kolver’s K-DUCER. 
First of all, all K-DUCER electric screwdrivers are already shipped with an ISO17025 calibration certificate.
Secondly, if regular in-house calibration is needed, then one of our standard torque testers like our new K-TESTER makes the process quick and painless. As with other tools, we recommend validating your drivers every year. If ISO or NIST certification is needed for both the screwdrivers and the torque testers, and in-house setup is not possible, then using a specialized lab will be necessary, as outlined below.

• Third-party calibration services 

In general, we always recommend our clients follow ISO standards, and it is important to note that any calibration certificate included with tools shipped from our factory will expire after 12 months. 

At this point, if you lack the setup or expertise to do your own calibration work, you can opt to use a third-party calibration lab or service provider. These companies specialize in the calibration of industrial tools and equipment and have the expertise, equipment, and certifications necessary to provide accurate and reliable calibration services, traceable to international standards such as ISO and NIST.

No matter which calibration method is chosen, it's important to ensure that it meets regulatory requirements and provides accurate and reliable results.
Kolver recommends that at a minimum you check your torque tools at least once a year using a calibrated torque tester.
By default, Kolver’s torque testers come with a certificate of conformity to EU standards but if ISO/NIST is required we will provide it at an additional cost through one of our lab partners.
As mentioned before, our K-DUCER line of transducer-based torque tools does ship with ISO certification out of the box, but as with any ISO certification, it will run out after 12 months. 

Properly maintained and calibrated torque screwdrivers will deliver accurate and reliable torque and angle readings, which is essential for maintaining product quality, worker safety, and regulatory compliance. 
If you need help, contact us and we will be happy to guide you through best practices and regulations, and help you find a suitable calibration schedule for your needs.