Structure and Function
of LOKRING Connectors

The Theory -

LOKRING Technology takes advantage of the fundamental laws of physics, material properties and basic engineering principles to arrive at an elegant design for joining tubes of similar or dissimilar materials. A LOKRING Union Connector consists of two LOKRINGS pre-assembled onto a tubular body with a light press.

During assembly of a LOKRING Connection, the tubes to be joined are inserted into the connector up to an internal stop. The LOKRING Assembly Tool is then used to apply pressure to the connector causing it to compress and complete the connection. This is a quick and simple method of joining tubes that eliminates the fire hazards of brazing and proper torque concerns of threaded connections.

The Connection -

The special inner profile of the LOKRING Connector causes the diameter of the LOKRING body to be reduced until it is in intimate contact with the outer surface of the tube that is being connected. This grip creates a metal-to-metal hermetic seal with a slight reduction of the tubes. This reduction causes no detectable drop in pressure or flow rate.

The radial forces of the tube and the connecting body resisting reduction are directed to the outside. And the radial forces of the LOKRINGS resisting expansion are directed to the inside causing a state of equilibrium known as elastic strain pre-load. This equilibrium is maintained for the life of the LOKRING Connection.

Pressure Area -

LOKRING Connectors are designed for a maximum operating pressure of Pn = 50 bar (750psi and a testing pressure of Pp = 4 x Pn = 200 bar (3000 psi). LOKRING Connectors can be used in a temperature range between -50ºC and +150ºC (-58ºF and +302ºF).

The expansion or contraction of the material caused by a change in temperature has no impact on the elasticity of the tube connection. Burst test have shown that the LOKRING Tube Connector is stronger than the burst point of the tube.