What is the SKF MB 21 lock washer used for?

It is used to reliably secure a lock nut on a shaft or sleeve and prevent it from loosening.

What are the dimensions of this lock washer?

It has an inside diameter of 105 mm and an outside diameter of 145 mm.

Which lock nut is compatible with the SKF MB 21?

This lock washer is designed for use with a KM 21 lock nut.

How does the locking mechanism work?

The inner tab fits into the shaft keyway, and an outer tab is bent into one of the nut slots.

Can you reuse a lock washer after disassembly?

No, SKF recommends installing a new lock washer every time the lock nut is mounted.

SKF MB 21 lock washer for lock nuts 105 x 145 mm

Supplier number: SKF MB 21 | EAN 7316577011640

Recommended Retail Price €18.26

8.95 tax incl.

€7.40 excl. VAT (incl. all environmental contributions)

On stock - immediately available | we have 3 products in stock.

Delivery by DHL

↓ Documents (1) ✆ Talk to a specialist

Reliable shaft locking with Skf MB 21

Practical benefits

Prevents unintentional loosening: You securely lock KM series lock nuts by bending one of the outer tabs into the nut slot.
Accurate fit and dimensions: Engineered with a 105 mm inside diameter and 145 mm outside diameter for proper positioning.
Simple and secure installation: The inner tab engages directly into the shaft keyway to prevent rotation during operation.

In a nutshell

The right choise for

With the Skf mb 21 lock washer, you securely lock km 21 lock nuts onto shafts or adapter sleeves to prevent unwanted loosening. Designed with a 105 mm inside diameter and a 145 mm outside diameter, it offers an exact and dependable fit. The inner tab engages directly into the shaft keyway, while bending an outer tab into a nut slot creates a positive mechanical lock. This keeps your assemblies firmly in place even under severe vibrations and dynamic loads, preserving optimal bearing preload. Ideal for mechanical maintenance, machinery assembly, and rotating equipment servicing.

Product information FAQ

€8.95

In stock - tax incl.

Key features according to our expert

Inner diameter: 105 mm
Outer diameter: 145 mm

Product description

MB and MBL lock washers are locking devices, used to secure KM, KML and HM .. T lock nuts onto a shaft or adapter sleeve and prevent unintentional loosening. MB .. A is a stronger version of the MB washer. The lock washers engage a keyway in the shaft or adapter sleeve thread. They lock the nut in position when one of the washer tabs is bent into one of the slots in the outside diameter of the lock nut. A new lock washer should be used each time the corresponding lock nut is installed.

Simple, stable and reliable fastening element
Easy to install and remove
Used for KM, KML, and HM .. T lock nuts

Documents

⤓ Technical data sheet PDF

All Features

Inner diameter: 105 mm
Outer diameter: 145 mm
Outer diameter: 145
Bore diameter: 105
Locking device: Lock washer

Brand SKF
01230646
EAN 7316577011640
Supplier number SKF MB 21

Frequently asked questions about this product

Answered by specialists

What is the SKF MB 21 lock washer used for?: It is used to reliably secure a lock nut on a shaft or sleeve and prevent it from loosening.
What are the dimensions of this lock washer?: It has an inside diameter of 105 mm and an outside diameter of 145 mm.
Which lock nut is compatible with the SKF MB 21?: This lock washer is designed for use with a KM 21 lock nut.
How does the locking mechanism work?: The inner tab fits into the shaft keyway, and an outer tab is bent into one of the nut slots.
Can you reuse a lock washer after disassembly?: No, SKF recommends installing a new lock washer every time the lock nut is mounted.