Pre-applied locking patches (nylon-patch screws)

Pre-applied thread locking screws — locking types

Pre-application means applying material to a fastener before installation. In a nylon version, material on part of the thread increases resistance as the screw turns in the mating thread. This mechanism differs from a curing thread adhesive. Not all pre-applied coatings should be treated as the same locking method.

Microencapsulated MK and nylon KLF pre-application

The DIN 933 category is divided into microencapsulated 267-27 MK and nylon 267-28 KLF pre-application. The microencapsulated version works by adhesion, while nylon mechanically increases rotational resistance. Selection, installation conditions and reusability must be established for the specific system.

Choosing a screw group in the catalogue

The category is divided by the designations DIN 933, DIN 912, DIN 7991, ISO 7380, ISO 7380-2 and DIN 7985. This lets you start searching with the version specified in the equipment documentation. However, the base screw designation does not define all parameters of the applied locking material. Check the locking details separately in the description of the specific product.

What should selection take into account?

• Thread and length: match screw diameter, pitch and length to the connection.
• Head and drive: check space for seating the head and access for the installation tool.
• Material and class: match the screw properties and coating to the design requirements.
• Pre-application position: the locking layer must engage with the mating thread over the appropriate section of the connection.
• Operating conditions: check the permissible temperature, chemical contact and installation requirements.

Installation and reuse

The driving resistance caused by nylon must be taken into account when establishing the installation procedure. It does not replace correct tightening of the connection. Reusability and the permitted number of cycles depend on the specific solution and its documentation. Do not assume one value applies to all screws with pre-applied locking material.

Questions about pre-applied thread locking screws

Is a screw with nylon made of plastic?

The term “screw with nylon” refers to the nylon thread locking material. Check the material of the screw itself on the selected product page.

Does coating colour define its parameters?

Colour alone is insufficient to establish operating temperature, rotational resistance or reuse rules. The designation of the applied system is required.

What should an enquiry to NERON in Piła include?

Prepare the screw standard, thread size, length, material, class, quantity and locking requirements. If reproducing an existing connection, include the part designation or its documentation.