HAM-LET ONE-LOK® is designed to provide leak-proof, secure connections that can withstand high pressure, vibration an vacuum applications. To this end, ONE-LOK® tube fittings are made up of three parts that are precision engineered and machined: body, ferrule and nut.

ONE-LOK® is designed for use in control systems, process and

instrumentation devices and in industrial equipment used in

various applications. For example:

ONE-LOK® offers a simple, high-quality tube fitting with excellent performance and reliability.

Owing to the single ferrule design, HAM-LET ONE-LOK® tube fitting continues to perform through repeated remakes; the ONE-LOK® single ferrule seal is leak-tight - remake after remake.

To ensure the installation of safe, leak-free systems, it is important to choose the appropriate ONE-LOK® single ferrule for your application. ONE-LOK® fittings are engineered to the highest standards.

The table below lists tube sizes, which have been tested to bursting pressure with both maximum and minimum wall thickness.

Correctly assembled ONE-LOK® fittings were installed and no leaks or other failures were noted at the connection points. If you plan to use tubing with different wall thicknesses than those noted in this chart, please contact the HAM-LET Technical Department for advice regarding the appropriate working pressure.

Note: Use fully annealed, high-quality stainless steel tubing of ASTM A269 or of equivalent standard. Working pressure: Based on laboratory and field tests using ASTM A269 tubing with a safety factor of 4:1 in a metal temperature range of -20º to +100ºc. However, it is the customer’s responsibility to ensure safe product selection that is based upon the total system design and function.

1. Insert the tubing into the ONE-LOK® fitting. Check 

that the tube rests firmly on the fitting shoulder and 

that the nut is finger tight.

2.  Tighten the nut. 1-1/4 turns of the nut is required for

To attain a leak free connection, the tubing must be cut squarely. A good quality tube cutter with an appropriate blade for tubing material is recommended.

Do not try to reduce the time of cutting by taking deep cuts with each turn of the cutter. This will work harden the tube.

The end of the tube must be deburred to avoid damage to the fitting and to ensure that the tube reaches the bottom of the fitting.

In order to cut the tube with a hacksaw and get square ends, the tube must be cut with guide blocks.

This method of cutting necessitates deburring of the tube ends.

Do not hold the tube in a vise in the place where it will be inserted into the fitting (the vise will leave a mark on the tube that may cause leaks, and might cause ovality).

Scratches on the tube might cause leaks. It is therefore important to handle the tube carefully to reduce the risk of leaks.

Example

ONE-LOK® fitting part numbers are constructed from symbols that identify the type of material and size of the fitting.

The ONE-LOK® part numbering system is the same as our LET-LOK® Tube Fittings, with the exception that you add an “H” between the prefix number and the “L” to designate the one ferrule design.