HEICO-LOCK® Ring Lock Washers

NEW: HEICO-LOCK Ringsicherungsscheiben

HEICO-LOCK® ring lock washers provide high-quality, user-friendly bolt securing for the most demanding of applications and are ideal for repeated use. The ring locking system guarantees that the two wedge lock washers are always fastened in the correct position with the wedge shaped cams on the inside and the radial teeth on the outside. This means that the bolt locking system is always easy, safe and quick to install, even for non-specialist users.




Design of the Ring Locking System

HEICO-LOCK® ring lock washers are supplied pre-assembled. The ring locking system consists of a polyamide ring (PA) and the already familiar HEICO-LOCK® wedge lock washers. Whereas the wedge lock washers secure the bolted connections reliably, the ring holds the two individual washers together in the correct position permanently.


  • Very easy to install and remove (ring locking system is supplied pre-assembled)
  • Proven system for securing bolts, at high as well as low preloads
  • Particularly suitable for dynamic loads – including when lubricants are used
  • Reusable with no reduction in quality or convenience
  • Also suitable for use with high-tensile bolts of 8.8, 10.9 and 12.9 and their respective nuts
  • Available in steel or stainless steel with a narrow or wide bearing surface


Technical specifications


1. Pre-assembled locking system

  • HEICO-LOCK® ring lock washers are supplied pre-assembled and offer the user the clear benefit of always being in the correct locking position – particularly important if being installed and removed repeatedly

2. Polyamide-Ring

  • The plastic ring on HEICO-LOCK® ring lock washers is made from polyamide (PA)
  • Other materials can be used for specific applications on request

3. Difference in hardness: HHEICO > HMaterial

  • The surface hardness of HEICO-LOCK® ring lock washers is greater than that of structural grade and high tensile bolts (8.8,10.9,12.9)
    • Steel (through-hardened) 485 ±25 HV0.3
    • Stainless steel (surface-hardened) > 520 HV0.05

4. Difference in angles: α > β

  • The wedge angle (α) between the HEICO-LOCK® ring lock washers is greater than the pitch (β) of the bolt thread
  • This angle means the expansion in thickness of the HEICO-LOCK® ring lock washers is greater than the possible longitudinal movement of the bolt along the thread

5. Difference in friction: μa > μi

  • The wedge-shaped surfaces have a considerably lower friction coefficient μi than the toothed outside of the washers (friction coefficient μa)
  • Loosening caused due to dynamic loads causes movement between the two washers in the region of the wedged surfaces

6. Difference in preload: Fdyn > Fstat

  • An expansion in thickness of the HEICO-LOCK® ring lock washers as a result of loosening leads to an increase in the clamping force
  • This causes an increase in the preload compared to when in a static state and thus causes the bolt to self-lock


Installation examples

Hexagon bolt in a through-hole,
secured on both sides
  Hexagon bolt secured
in a blind hole
  Countersunk socket head bolt
secured in position
  No locking function when
combined with flat washers





Product overview

Stainless Steel
Internal Ø
External Ø
Per pack
M4 #8 HLRB-4 HLRB-4S 4,4 9,0 200
M5 #10 HLRS-5 HLRS-5S 5,4 9,0 200
M5 #10 HLRB-5 HLRB-5S 5,4 10,8 200
M6 - HLRS-6 HLRS-6S 6,5 10,8 200
M6 - HLRB-6 HLRB-6S 6,5 13,5 200
- 1/4" HLRB-1/4" HLRB-1/4"S 7,2 13,5 200
M8 5/16" HLRS-8 HLRS-8S 8,6 13,5 200
M8 5/16" HLRB-8 HLRB-8S 8,6 16,6 200
M10 - HLRS-10 HLRS-10S 10,7 16,6 200
M10 - HLRB-10 HLRB-10S 10,7 19,5 200
M12 - HLRS-12 HLRS-12S 13,0 19,5 200
M12 - HLRB-12 HLRB-12S 13,0 25,4 100
- 1/2" HLRS-1/2" HLRS-1/2"S 13,5 19,5 200
M14 9/16" HLRB-14 HLRB-14S 15,2 30,7 100
M16 5/8" HLRS-16 HLRS-16S 17,0 25,4 100
M16 5/8" HLRB-16 HLRB-16S 17,0 30,7 100
- 3/4" HLRS-3/4" HLRS-3/4"S 20,0 30,7 100
- 3/4" HLRB-3/4" HLRB-3/4"S 20,0 39,0 100
M20 - HLRS-20 HLRS-20S 21,4 30,7 100
M20 - HLRB-20 HLRB-20S 21,4 39,0 100
M24 - HLRS-24 HLRS-24S 25,3 39,0 100
- 1" HLRS-1" HLRS-1"S 27,9 39,0 100

Non-standard sizes and special materials on request.
For a wider range of products, we recommend our HEICO-LOCK® wedge lock washers.