The Truth Behind Holmatro Cutting Performance

15 Jul 2013

During my recent visit to Australia I witnessed a presentation from Holden Motors, during which an engineer gave details of how they have constructed their new Commodore VF model. They have used more Ultra High Strength Steel (UHSS) in areas which adds stiffness, whilst at the same time reducing weight and increasing fuel efficiency.

When details of the increased use of UHSS were shown, there were people in the room who audibly said “We won’t be able to cut that!!”

The New Holden VF Commodore makes use of more UHSS.jpg
The New Holden VF Commodore makes use of more UHSS

This is the kind of reaction I am becoming more and more used to when the topic of UHSS is raised.

Following the input from Holden, I gave a keynote speech during which I showed a video of me using Holmatro cutters to cut the latest Golf Mk7. The video clearly shows me cutting at approximately 250 bar pressure (around 35% capacity). The B pillar on the new Golf has a tensile strength of over 1000Mpa (actually nearer 1300Mpa) - SEE VIDEO BELOW

The New Golf Mk7 A and B Pillars well above 1000Mpa.jpg
The New Golf Mk7: A and B Pillars well above 1000Mpa

Following my presentation I continued with a hands on session where we cut the new Holden Commodore at less than 300bar. We did this by inserting a pressure gauge between the pump and the tool, a very clear indication of how hard your tool is working.

Let’s be clear. Cars HAVE become stronger over the last decade. Technology now allows these steels to be made stronger, whilst still allowing vehicle manufacturers to shape and form it into the desired shapes.

But let’s be clear on another point. If you have the right tool for the job, new vehicle construction does not offer a challenge. It is important to point out that cutting at 35% capacity means that you have 65% in reserve.

In fact what we ALSO proved during the hands on session is that exposing the interior trim on new vehicles is now more difficult than ever. As we MUST do this before we make any strategic cuts, it's tasks such as this that lead to extended time on scene and slowing down of the extrication process. Full, casualty centred exposing of the interior trim took over 2 minutes (for one side) and these are the kinds of areas that are overlooked when we train for extrication.

Cutting a Brand New Golf Mk 7

This Video shows CU4055 cutters cutting the new Golf Mk 7 bodyshell. The maximum pressure reached is 300 bar which is during the cut on the lower B pillar (0.38sec). This 300 bar is only for a very short period while the construction is being compressed. The ACTUAL cutting pressure is around 240 bar.

The increased use of UHSS of course means that cars are stronger. BUT we must put this increase in strength in context. If we are cutting brand new construction at around 35% capacity, we can afford to focus on other areas which are genuinely creating problems and leading to extended extrication times. The use of an inline pressure gauge is a great way to see how your tool is working....try it.

As usual I welcome your feedback.


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