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Watch the new Junker test video here!

Nord-Lock washer junker vibration test video

We are pleased to present our brand new Junker test video. It is now available on the Nord-Lock Group YouTube channel, and also embedded below:

The Junker test, according to DIN 65151, is considered the most severe vibration test for bolted connections. In this video we compare the performance of Nord-Lock washers with other locking methods.

Interested in learning more?


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  • Fadil Ayash

    26 April 2018

    I am an old mechanic i love what i saw . thank you


    23 April 2018


    what is the Aplitude, Frequency and duration kept fpr carrying vibration test done on M 27 Nord lock washers with junker test

  • Martin Medved

    11 April 2017

    What is the minimum required M8 screw extension by preload (after setting) in order to ensure the Nordlock active?

    • Evan (Nord-Lock Group)

      21 April 2017

      Hi Martin, we have replied you via email.

  • Michael P Graham

    03 April 2017

    In responce to Sonny’s comment on June 1st 2016: Watch your own product video at 4:15 and tell me Nord-Lock doesn’t mar the clamped surface.

    • Evan (Nord-Lock Group)

      27 April 2017

      Hi Michael, Nord-Lock washers do create impression marks but they are harmless to the surface and it is also a way to verify our locking function.


    21 March 2017

    I need Nord lock washer – ID Ø6.5 x OD Ø10.8 x 1.8Thk.

    • Evan (Nord-Lock Group)

      23 March 2017

      Hi Mariyappan! We have sent you an email. We look forward to hear from you.

  • how about this compare to lock nut?

    • Harlen (Nord-Lock Group)

      12 January 2017

      Hi Melvin, Nord-Lock washers utilise the wedge-locking function incorporated in the washer design to secure joints whereas lock nuts of various types utilise friction to secure joints. Securing by friction is not reliable and furthermore having high friction in a joint is a huge disadvantage. Since Nord-Lock washers do not rely on friction to secure joints, lubrication can be used before installation. It is good practise to lubricate the fastener threads and under the bolt head or nut (tightening side) before tightening the joint. That would minimise friction scatter and preload variation in the joint.

  • julio cesar campo rengifo

    27 December 2016

    necesito referencias y contacto en la ciudad de Cali, Colombia

  • George Mavroidis

    26 December 2016


    Very good Job. There is some distributor in Greece?

  • Hans Carlström

    16 December 2016

    I am working for Volvo Bus, and I´m intressted to know more about the washer due to problem we have with eart cables come loose on one of ower bus models due to heat. Do the washer lead current?

  • Francois Masse

    13 December 2016

    Good day is this product CSA approved ( CANADA) and if so do you have a distributor in Quebec?

    • Evan (Nord-Lock Group)

      14 December 2016

      Hi Francois, we will contact you shortly via email. Thank you.

  • This is such a great video!
    So smart, informative and selling!


  • jabbar hassan

    05 December 2016


    I would like to know your terms and condition to obtain the middle east exclusive distributed for nord locking washer junker

    my contact details are

    • Evan (Nord-Lock Group)

      08 December 2016

      Hi Jabbar, we will reply to your inquiry via email.

  • Are your Nord-Lock Wedge-Locking Washers intended as a single use item or can they be reused?

  • Balachandran

    29 September 2016

    what is the thumb rule for small screw torque. how to set the grub screw torque based on the bolt.

    • Harlen (Nord-Lock Group)

      11 October 2016

      For any screw, it is recommended to use its full capacity, no matter the size, based on the maximum work load on the joint. A rule of thumb is to stress the screw up to between 60 – 80% of its yield strength. Whether the achieved bolt force is enough for the specific application depends on the application’s work load (force). If a higher preload is needed due to the specific work load then a larger or stronger screw should be chosen in order to get the required preload.

      The torque needed to tighten a joint depends very much on the thread and under head friction. The thread size, pitch and geometry of the screw also play their part. Usually such friction values are given in screw catalogues and engineer handbooks. If you need a more accurate tightening then an estimation should be made using one of the formulas like Kellerman & Klein, Rotzler, etc., and insert the friction values, thread size, pitch and friction area under bolt head/nut in the calculation. Many large companies have the resources to do tests to find out the friction values of the fasteners they use in order to achieve, for them, an acceptable accuracy in their estimations.

      Screw manufacturers do provide torque values for their screws but these are very general estimations. The friction value under the bolt head actually differs depending on what washers you are using and whether you are using any washers at all. It also depends on whether a lubricant is used under the bolt head/nut and bolt thread. Lubricants help to decrease friction scatter whereby a smaller preload deviation can be achieved.

      When Nord-Lock washers are used, the friction under the bolt head is known because sliding is always between the bolt head/nut and Nord-Lock washers. The Nord-Lock washers never slide on the clamped part. That is the reason why we are able to provide torque guidelines with, in most cases, acceptable accuracy.

      Lastly, a good and accurate tool must be used for the tightening. For torque tightening we recommend a calibrated torque wrench.

  • Amazing video, watching this video made me think how really important it is to select a correct washer/nut for my tool instead of using a nylon inserted all the time. Thanks!!

    • Evan (Nord-Lock Group)

      06 September 2016

      Thank you and you have made a great point. Glad that you like the video!

  • Just sat through a 2 day course on this at work and used the Junker machine on the same hardware shown. The Nord-Lock was by far the best at holding clamp load.

  • Will the effect of Nord-Lock washer remains same when used with Plain washer to protect mounting surface ? Thanks in advance !

    • Frida (Nord-Lock Group)

      03 June 2016

      Thank you for your comment. You should not use the Nord-Lock washers on top of a plain washer that can rotate because then rotation can occur between the plain washer and the underlying surface and the locking effect you wish does not remain. The serrations of the Nord-Lock washer make impression marks but they are harmless to the surface. The impression marks verify the wedge-locking function since sliding will occur where friction is lowest, i. e. between cams. If you have any further questions, please contact us at

  • Steve Beert

    25 May 2016

    I see you never tried a flange nut. They retention marks on nut to keep them from turning. They work well.

    • Sonny (Nord-Lock Group)

      01 June 2016

      A flange nut with or without serrations is a friction locking method. The serration will only increase the friction between the nut and the contact surface. If there is vibrations or dynamic loads then there will always be a risk that the nut or the bolt will start to rotate and loose clamp load. There are many different types of serrated flange nut on the market, unfortunately we are not sure which is the specific one you mentioned.

      If the tightening is made on the nut side and the nut have serration, then you will damage the contact surface during tightening and untightening.

  • Jyotirmoy

    01 May 2016

    Huck bolt is the best so far..

    • Harlen (Nord-Lock Group)

      03 May 2016

      Thank you for the comment. Huck bolts are for permanent joints, like rivets, which means the only way to remove them is by cutting them. They have a couple of advantages, quick installation and installation can be done from one side without the need to hold the other side for a through hole application. However, you need special tools for the installation. If the application is a permanent joint (no need to remove), has very small or no work load (static) and does not need accurate tightening, then Huck Bolt may be a solution.

      Critical joints demand accurate tightening at specific preload level. An application with dynamic work load and/or thermal loading, applying the correct preload is vital. It will decrease the impact of the external work load variation on the bolt and thus significantly decrease the alternating stress of the bolt thereby prolonging its fatigue life. A good way to achieve the correct preload is to lubricate the fasteners and tighten the joint with a calibrated torque wrench at the specific torque for the specific application. An accuracy of ±10% or better can be achieved with this type of tightening.

  • Amazing Technology! Thanks

  • All these years I thought Nyloc or ESNA nuts were the best. What a difference and this video shows it!

  • Kenneth Andersson

    01 January 2016

    A very interesting video showing what each nut doing under vibration, this change my mind of other type of locking advise . This is what it should be the new type of Nord-lock washer, I like it.


    Kenneth Andersson
    Tryon, NC.