Multifunctional wedge-locking

A new evolution in bolt security

There are two main reasons why bolted joints fail: spontaneous bolt loosening and slackening. Traditionally, application design has involved trying to figure out which will have the biggest effect on the joint and choosing a solution to handle that one problem. It is a difficult compromise to make, especially when both could cause application failure.

Now, you can count on one solution to meet all your bolt securing needs. Introducing the new Nord-Lock X-series washers — for bolt security without compromise.

  • Nord-Lock’s multifunctional wedge-locking solution combine unrivaled wedge-effect to prevent spontaneous bolt loosening with an exceptional spring effect to compensate for loss of preload due to slackening, giving total security for those situations in which there can be no compromise.

Bolt security without compromise

Utilizing a unique multifunctional design, Nord-Lock X-series washers offer the highest security against both spontaneous bolt loosening and slackening.

 

Further reading:

A new dimension of safety

Upon tightening the fastener, the washers flatten and the serrations engage the contact surfaces. Since the cam angle (α) is greater than the thread pitch (β), the wedge-locking effect will prevent any rotation of the fastener. Directly after tightening, the joint settles and the fastener sinks into the surface material. The washers immediately deflect and the spring effect (Fs) counteracts the slackening movement of the bolt, thereby preventing loss of preload on the joint.

These multiple functions continuously act on the bolted joint to maintain preload and prevent spontaneous bolt loosening — serving as an effective solution for vibration, dynamic loads, settlement and relaxation.

Further reading:

 

Benefits throughout your application’s lifespan

Below you find a selection of advantages with Nord-Lock multifunctional wedge-locking solution.

Design

  • Simplify design for demanding applications with a single solution that secures against both spontaneous bolt loosening and slackening.
  • Save costs by using one solution for all bolt securing needs.

Assembly

  • Save time with quick and easy installation using standard tools.
  • Facilitate inventory and logistical savings due to reduced item numbers.

Operation

  • Achieve increased operational reliability while significantly reducing the risk of unplanned production stops, accidents, and warranty claims.
  • Invest money and time in profit-generating tasks rather than retightening procedures.

Maintenance

  • Decrease maintenance time with simple disassembly.
  • Save time and money with a reusable solution, especially in industries with difficult access to the bolted joint.
  • Nord-
Lock personnel performs over 10,000 live Junker vibration 
tests around the globe every year.

Proven in Junker vibration test

The Junker test, according to DIN 65151, is considered the most severe vibration test for bolt connections. The test exposes the joint to transverse movements underneath the bolted head/nut, while continuously measuring the clamping force.

The Junker test shows that Nord-Lock’s wedge-locking function safely secures the bolted connection, which is verified through the clear increase in tension during untightening. The Nord-Lock X-series kept the highest initial tension thanks to its additional spring effect.

Would you like to learn more about the performance of Nord-Lock X-series washers? Contact your nearest representative through 
Contact us.

  • With the development of new materials and techniques - such as corrosion-resistant composites - slackening is a common problem due to settlement and relaxation.
  • Applications in heavy industries are constantly subjected to external forces, putting bolted joints at risk for spontaneous loosening due to vibration and dynamic loads.

The only solution that handles both loosening factors

To see how different products function in various circumstances, we can look at the evolution of preload in a bolted joint over time. The graph below illustrates the performance of traditional bolt securing products with composite materials. The diagram shows two phases: a static phase in which settlement is measured (over the period of 4 hours) and a dynamic phase when vibration is added (measured in 30 seconds). Compare how each of the solutions counteracts slackening and handles vibration.

Problems start as soon as the preload falls outside the functional range. If the preload is too high, yielding occurs. If it is too low, there is separation or sliding between the parts. Only Nord-Lock multifunctional wedge-locking solution keeps you within the optimal limits.

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