Definition of the use of

What is Lokring?

Lokring is a mechanical method for producing permanent weld equivalent pipe connections, eliminating the need for hotwork and the associated health and safety issues.
Lokring are patented fittings, they are permanently join small diameter nominal pipe size (1/4 thru 3) and tube (1/4" thru 2") without threading or welding.

Following insertion of the pipe or tube end into the fitting, hydraulic tooling is used to advance each swage ring axially over the fitting body, radially compressing (swaging) the fitting body on to the outside diameter of the pipe or tube.

Patented Elastic Strain Preload (ESP®) technology

The leak-free seal is the result of LOKRING's ESP installation where the axial movement of the LOKRING driver over the body swages the body onto the pipe's surface. This compresses the pipe wall first elastically and then plastically.

The pipe wall resists this swaging action, generating high unit compressive loads at the contact points between narrow sealing lands inside the fitting body and the pipe surface.
These contact stresses are sufficiently high to plastically yield the tube surface under the sealing lands, forming a 360° circumferential, permanent, metal-to-metal seal between the pipe and fitting body. The driver, which experiences a small increase in diameter (elastic strain) during installation, exerts an elastic, radial pre-load on the metallic seals for the use of the connection.

Lokring approvals

LOKRING meets or exceeds the following technical specifications, standards and approvals:

Lokring general

Examples Pressure Rating for Stainless Steel Pipe Fittings:

Lokring products can bring significant benefits in both new installations and maintenance applications, enabling pipework installations up to 70% faster and cost saving of up to 70% compared to welding.

Source April 22 2014: