Munji Trailer Recovery Link - Destructive Test Results Posted on 30 Mar 21:34 , 0 comments

A huge thanks to our new friends at MechTest - Brisbane Laboratory for conducting the destructive testing of the soon to be released Munji Trailer Recovery Link.


Trailer Recovery Link Body (Blue Component)

The point of failure was 107.61 kN (10,973.16 kg) of force applied to the tow ball connection. Due to the tow ball connection failing at just under 11 tonne, the Trailer Recovery Link could not be tested any further. 

The test demonstrated that our Trailer Recovery Link exceeds the strength of a 3.5 tonne rated tow ball.

The images below demonstrate the test, being a simulation of a trailer hitch pulled tight to the point of near destruction (see how the tow ball is bent on an angle). Further inspection shows elongation and shearing of the threaded shaft and destortion of the mounting surface of the ball attachment.

There was no destortion, or elongation to any section of the Trailer Recovery Link. The only damage detected were scratches to the anodised surface. 

A custom made testing fixture (see image below) was manufactured by MechTest. The texting fixture was mounted to the lower section of the tow ball, as this is the strongest part of the ball (noting this is not how a tow ball is used), as we wanted to try and obtain a failure in the Trailer Recovery Link (in order to know its destruction point).

Destructive test of the Skid/Safety Chain Sadle Plate (Grey Component)

The point of failure for this part was 28.59 kN (2,915.37 kg) of force applied.

Testing was halted at this stage due to the significant yielding of the holes during the test (see images showing elongation of the holes').

This testing was conducted to simulate the situation of trailer safety chains pulling on the holes i.e. the secondary safety system.

Material Testing - Conducted by Aviation and Industrial Inspection Services

In addition to the above, the Trailer Recovery Link also underwent an Eddy Current and Ultrasonic test.

The purpose of this test is to assess the alloy material itself, to check for imperfections e.g. microfractures, porosity, i.e. anything that could weaken the metal. 

The test passed, meaning no imperfections were found in the material.


The Trailer Recovery Link has been slightly amended to allow for the fitment of a McHitch coupling. This means ALL tow couplings that use the standard bolt on attachment (i.e. tow ball, McHitch, poly block, D035, AL-KO pin) will suit this part.

In addition to the Trailer Recovery Link, the following plates will be available for purchase:-

1. Small 'Compact' Plate - Made from 304 Stainless Steel. Made from stainless steel, this is the strongest of the two 'plate' options;
2. Large Plate - Made from 6061 Alloy, made to suit softer surfaces such as mud. Alloy was used for the large plate in order to reduce weight;
3. Poly Plate Cover - to be applied to either the small plate or large plate as an optional consumable protective covering, and to also prevent damage to surfaces such as boat ramps (so you can avoid any Council fines).

We are happy with where our testing has taken us and production will start soon.

Please stay tuned for the release update.

Stay safe.