04.11.2010
Big crawler tips
We have been trying to ascertain the facts of a large crawler crane accident in the UK for a week now and still know little more than the basic facts.
We received several reports that a 300 tonne Liebherr LR1300, owned by Weldex, had tipped over on a wind farm project in South Wales on Thursday last week, while our editorial team was in Bologna for SAIE.
Early information said that the crane had tipped over after the road it was travelling on had given way under one of the tracks.
In the time since the accident all we have been able to discover is that
a) the accident definitely occurred on the Maesgwyn site near Neath, Port Talbot b) that it was travelling between turbine sites and c) that no one was seriously injured.
We also know that the HSE has been on site, investigating what happened.
We are still waiting for a statement from Weldex who have spoken to us but not yet divulged any details.
We have also discovered that a similar accident occurred with a Terex crawler crane last year in Scandinavia. The crane, reportedly a Terex CC2800NT narrow tracked crawler tipped over when the road underneath it gave way in a similar manner to the most recent case.
UDATE
We can now confirm that the accident occured on the Maesgwyn wind farm site, where Walters UK is installing 13 x 26MW turbines. The HSE has provided us with a statement:
"The HSE was informed of the incident and did visit site to see the crane. It appears that the crane was being moved from one lifting site to another site within a large forest. The crane was being used on the construction of a wind farm."
"The crane was fully rigged and ballasted and travelling on a forest road. The driver got very close to the edge of the road on a bend. There was also a land drain culvert under the road. The road gave way under the load of the crane. The crane tipped off the road into the surrounding forest."
"We have been told that the crane had been down the road several times in the past. The road was also used for HGVs delivering components."
Weldex has continued to decline all attempts from us to discuss the accident or for it to issue a formal, or even off-the-record, statement.
We have had reports from site stating that one of the tracks was fully retracted due to technical problems and the other partially extended, however the point of the LR1300W is that it can travel with tracks in the retracted position on wind farm roads. The following two photographs were taken a couple of weeks after the incident.
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A mobile phone shot of the overturned crane
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A closer look at the tracks
The crane was apparently moving while fully rigged at night, although the crane had several escort vehicles the operators view of the track/road woudl have been less than ideal we understand that on a ben in the road to the left he went too close to the edge causing the road to give way on that side and the crane to tip. The operator was able to exit the cab as it went over.
We have also been sent some very small/poor photos of KR Wind crane that went over in Sweden last year and are still working to obtain full details, but it looks as though that accident was very similkar to this one.
Vertikal Comment
Hopefully the full facts of this accident and the one last year will eventually come out, as it looks as though valuable lessons might be learnt. Sadly if those involved in last year’s accident had been willing to share the information more widely it might have alerted others of signs to look out for and who knows it may have prevented this accident?
Imagine an aircraft going down and the information on what happened being kept secret. It is true that in both of the above accidents there were no fatalities, however it could so easily have been different.
Silence is also probably mandated by lawyers and the safety authorities looking to apportion blame? However the sharing of accident or near miss details is one of the most practical ways the industry can make itself safer.
Lest anyone misunderstand us, we are not accusing anyone involved in last week’s accident of hiding anything – it is too soon and we know that in the aftermath of such an incident publicising the fact is the last thing on your mind. And to date no one has specifically declined to speak to us - they are just never in and dont return calls.
However the same does not apply to last year’s incident where we have been told that there was a conscious effort to prevent information from being passed on rather than to share it with the indsutry as a whole.
We sincerely hope that the full facts of both this accident and the one in Scandinavia come out in the weeks ahead with recommendations of what can be done to try and avoid such incidents going forward.
PS. Fortunately nobody was killed on this occasion, unlike Friday 15th January 1988, when my Father in Law David Stanford (d) was killed by an NCK Crawler Crane.
Good Evening Friends at Vertikal,
If your photos above are accurate, then the cause of this Crawler Crane would appear to be self evident. Please allow me to explain...
1. Crawler Cranes like the excellent Liebherr LR 1300 have a Hydraulic mechanism to adjust the overall width of the crane across the Tracks. The benefit of which is increased width for extra stability when lifting, or reduce width for improved access when travelling between trees or buildings or moving on site.
2. This allow the crane to travel with the two tracks in the fully extended position, or with both tracks in the fully retracted position. But not with one track fully extended on one side and the other partly retracted.
3. For to do otherwise is to divide the vertically imposed ULW load of the crane, jib and Ballast Blocks in an unequal manner between the two tracks. This means that the track that is partly retracted, then exerts more PSI ground pressure ( Or Kgs per Sq Cm) on the dirt road than the other fully extended track.
Furthermore, it also means that when travelling on an unlevel surface, that the crane is much more likely to tip over to the retracted side if...
(a) The ground slopes that way and...
(b) That is the side where the track is fully or partly retracted.
(c) Especially so on a dirt road with a Drain, Culvert or Ditch on the retracted side ( With None on the other) for that side of the dirt road will compress more under that track.
This is yet another example of Negligence by the Ops Director in charge of the Lift ( Not an Accident, as it was not Accidental). Because he or she never understood the physics of moving a Large Crawler Crane with One track fully extended, while the other track is partly retracted.
Please wake up to these Hazards quickly before any more innocents are killed, because to wait untill after the event leaves you and your MD open to a Manslaughter Charge.
FYI only, In English Law Manslaughter is defined as a Fatality arising from a Negligent or Unlawful act. That is with Actus Reus, but without the Mens Rea.( Latin terms applied by the Courts)
The Editor of Vertikal is to be applauded for his tenacious reporting of this potentially fatal event, which should not be covered up, despite the attempt to do so.
Kind Regards
Mike Ponsonby BA.
Fortunately nobody was killed on this occasion, unlike Friday 15th January 1988, when my Father in Law David Stanford (d) was killed by an NCK Crawler Crane.
Mark Krajci
Good to hear that someone understands the importance of reporting and following up on accidents.
It is too bad that the parties involved do not understand the learning path needed to prevent these accidents, perhaps it could save them some aggravation & money in the future.
Good job vertikal.net keep the reports coming those of us with some real knowledge & care will pick out the good and bad!