HARDLOCK Bearing Nut (HLB) – Torque Chart

hlb tightening torque table

Other Relevant content:

What wrench is required for installing bearing retaining nut?
  1. Spanner socket (4 pin) SKF TMFS
    & Torque wrench
  2. Spanner wrench socket ( hook wrench ) SKF HN

Please avoid the use of b ) Spanner wrench socket and use a spanner socket with a torque wrench when possible.

What is the installation process for HLB?
What is a second nut?
First of all, the first nut indicates the nut that is seated against the bearing or clamping surface.
The second nut is the locking nut installed after the first nut.
What nut should I install first?
Install the Convex Nut first for applications with preload.
Install the Concave Nut first for applications where the nuts face must be flush with the bearing inner ring face.
For both use cases, give caution to not strip the threads by installing with more torque than the threads can bear.


Torque Chart

Unit: newton meters (N·m)

Item no. Nominal diameter First nut tightening torque Second nut tightening torque
d × p (minimum)
HLB-01 M12 × 1 As per customer specification 16
HLB-02 M15 × 1 As per customer specification 28
HLB-03 M17 × 1 As per customer specification 37
HLB-04 M20 × 1 As per customer specification 55
HLB-05 M25 × 1.5 As per customer specification 80
HLB-06 M30 × 1.5 As per customer specification 115
HLB-07 M35 × 1.5 As per customer specification 130
HLB-08 M40 × 1.5 As per customer specification 155
HLB-09 M45 × 1.5 As per customer specification 170
HLB-10 M50 × 1.5 As per customer specification 200
HLB-11 M55 × 2 As per customer specification 210
HLB-12 M60 × 2 As per customer specification 240
HLB-13 M65 × 2 As per customer specification 255
HLB-14 M70 × 2 As per customer specification 270
HLB-15 M75 × 2 As per customer specification 300
HLB-16 M80 × 2 As per customer specification 310
HLB-17 M85 × 2 As per customer specification 340
HLB-18 M90 × 2 As per customer specification 350
HLB-19 M95 × 2 As per customer specification 380
HLB-20 M100 × 2 As per customer specification 390
HLB-21 M105 × 2 As per customer specification 410
HLB-22 M110 × 2 As per customer specification 415
HLB-23 M115 × 2 As per customer specification 420
HLB-24 M120 × 2 As per customer specification 435
HLB-25 M125 × 2 As per customer specification 440
HLB-26 M130 × 2 As per customer specification 450
HLB-27 M135 × 2 As per customer specification 455
HLB-28 M140 × 2 As per customer specification 465
HLB-29 M145 × 2 As per customer specification 470
HLB-30 M150 × 2 As per customer specification 480
HLB-31 M155 × 3 As per customer specification 485
HLB-32 M160 × 3 As per customer specification 500
HLB-34 M170 × 3 As per customer specification 600
HLB-36 M180 × 3 As per customer specification 700
HLB-38 M190 × 3 As per customer specification 800
HLB-40 M200 × 3 As per customer specification 900

Attachment and maintenance notes

  1. Normally, the convex (tightening) nut is the initial nut, but the concave nut may be used as the initial nut instead.
  2. Tighten the initial nut (convex or concave) to the torque required for the target application.
  3. Tighten the secondary nut to the minimum torque value set by Hardlock. This torque value is the minimum required to pass an impact vibration test conforming to NAS 3350/3354. Exceeding this torque value for full contact of the nuts is acceptable.
  4. The Hardlock Bearing Nut is manufactured with a thread tolerance class of 6H. Therefore, a 6g counterpart is required.
  5. If you do not tighten the initial nut, make sure that you use a wrench or some other tool to hold the initial nut in place when tightening the secondary nut. This will prevent the nuts from rotating together.
  6. The materials for our standard products are SS400 equivalent (low-carbon steel), S45C (medium-carbon steel) and SUS304 stainless steel, and S45C for our thin-type products.