Screw locking


Permanent and secure fastenings.
With RIPP LOCK® lock washers, nuts and screws.


For permanent joints

RIPP LOCK® guarantees lasting retention of preload force in the threaded connection, even under high dynamic stress.

RIPP LOCK® washers, screws and nuts are mechanical locking elements which are proven to prevent fasteners from working loose. The reliable locking effect is achieved by radial ribs which press into the material when the element is fastened.

Böllhoff parabola

Method / principle

When the fastener is screwed in place, the specially designed radial ribs of the RIPP LOCK® lock washers press into the mating face. The resulting form fit prevents the fastener from working loose.


RIPP LOCK® is used wherever there is a need for an effective and economical anti-rotation lock. It is also suitable for soft and coated surfaces, slotted holes and for product range standardisation.

Product benefits
  • Anti-rotation lock
  • Loading capacity up to property class 12.9
  • Gentle to contact surface
  • Multiple re-use
  • Corrosion-/heat-resistant

Product benefits

There are many good reasons for using our products.

Strength and options.
Point by point.

Excellent locking action

No slackening or working loose. Even under high dynamic stress your threaded connection stays tight.

Non-damaging to surfaces

Painted, galvanised, chrome-plated? RIPP LOCK® is especially suitable for delicate surfaces and soft materials such as aluminium, copper, and aluminium or magnesium casting alloys.

Easy to use

Simple fitting and removal of the washer, with multiple re-use possible. No curing times.

Independently tested

RIPP LOCK® has proved itself in industry. Confirmed by independent bodies and general type approval Z-14.4-664 as an effective anti-rotation lock.

Fully integrable

RIPP LOCK® can be retrofitted to almost any existing assembly. Thanks to standard outside diameter to DIN 125/ISO 7089 and a small outside diameter for countersunk screws.

Detailed description


The RIPP LOCK® screw lock

The key to security? The radial ribs. The contact angle at the foot of the ribs is significantly larger than the pitch angle of a metric thread, so any loosening of the fastening is countered by a rise in the preload force.


Design principle

When the fastener is fitted, the applied preload force presses the radial ribs of the RIPP LOCK® lock washers into the mating face. The resulting form fit reliably prevents the fastener from working loose, even under extreme vibrations or strong dynamic stress. Due to their high hardness, RIPP LOCK® washers can be used with screws of all property classes up to 12.9 inclusive.


The RIPP LOCK® screw lock features radial ribs

The RIPP LOCK® screw lock features radial ribs

Product variants

Every project deserves a tailor-made solution.

For that reason, RIPP LOCK® screw locks are available in a number of different versions.

Lock washers

Standard diameter

As a universal product, the RIPP LOCK® lock washer can be used almost anywhere – outside diameter in accordance with DIN 125/ISO 7089.

Lock washers

Reduced outside diameter

The locking solution for countersunk socket head screws.

Self-locking screws


The locking ribs engage with the entire contact surface of the screw.

Lock nuts


The locking ribs engage with the entire contact surface of the nut.



Find out more: related downloads.

If you would like to know more, simply download the relevant brochures.

Title Language Version File Download
RIPP LOCK® screw lock
English 09/2021 1051 kB / PDF
English 09/2021 1051 kb / PDF
Success story
Truck crane – Optimisation of a slew ring
English 0319/14.02 302 kB / PDF
English 0319/14.02 302 kb / PDF
Böllhoff bulletin
Securing Threaded Connections
English 1627/11.02 1218 kB / PDF
English 1627/11.02 1218 kb / PDF

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