For all you trainees who think 30 psi is safe....

[Shugster]

An American woman on holiday died after a wheel she had on her lap, (The boot was full), exploded as it was damaged...

http://news.bbc.co.uk/2/hi/uk_news/scotland/edinburgh_and_east/8600833.stm

Take heed young mechanics! These things can and do happen, 30 psi stored in a big vessel is a fair wedge of stored Energy.

And RIP to the USAF Captain, (As she was), too.

 

[Rocket_Ronster]

I still remember the story from around 20yrs ago(?) with some chavs going around screwdrivering tyres. All went well till head youth did a JCB back wheel. Only 28psi, but an awful lot of 28psi`s. God bless Darwinism.

 

[litterman]

We had a lorry last week blw a tyre on the main road (only the main road has only narrow kerbs no more than 2 footone of its wheelr blew out and also blew the frontage of a shop out (it hsa actualy a happened a few times).If there had been a mother and child level with tyre god know what would have happened

 

[Spearmint]

****ty death! I bet that made a right mess of her!

R.I.P

 

[Rigga]

To explain the force in a mere car tyre to my wife...

1. Draw a matrix of nine 1-inch squares (An OXO game square) on paper and place it on a desk.

2. Using any means available, place 30lbs of weight on one square without going outside the lines for that square.

3. Do the same on the other 8 squares adjoining that first square. (or imagine what all that weight will do to the desk!)

4. Having noted the amount of weight pressing on your matrix, remove the weights and place the matrix against any tyre of your choice and

5. Observe how many one-inch squares cover that tyre's surface area.

6. Try to imagine putting all that weight, per square inch, inside the tyre!

 

[duffman]

Anyone know why it went bang?

 

[Shugster]

Anyone know why it went bang?

It is thought the couple had changed the tyre on the BMW Z3, after noticing a bulge in it

Maybe they went through a large pothole that damaged it.

And the problem isn't just the pressure the real problem is that it's filled with a very compressable gas.

(We built a machine to use pneumatics for testing running shoes, but we had the devils own job to control it correctly mainly due to the amount of air we had to let in / out to change the loads quickly enough and the subsequent non linearities of the system... we binned the idea in the end).

 

[Shugster]

This reminds me of an incident at Brüggen in the tank bay.

The Tonka drop tanks were pressure tested after maintenance and were suppose to be filled with fuel first before being pressurised hence there would only be a small volume left to fill with air.

Of course over time people became lazy and in the end didn't bother filling them with fuel anymore and just used air....

..until the day came when one failed and a panel blew out thankfully not injuring anyone.

Maybe training should include showing the dangers of compreesed air be it a video or a more thought provoking live demonstration?

 

[monobrow]

Strangely, pressure was the key to a recent Mythbusters... Skip it on to 7:30 ish for a practical demonstration...

http://www.youtube.com/watch?v=V317VRQN0B8

 

[he_who_dares_rodney]

We had a lorry last week blw a tyre on the main road (only the main road has only narrow kerbs no more than 2 footone of its wheelr blew out and also blew the frontage of a shop out (it hsa actualy a happened a few times).If there had been a mother and child level with tyre god know what would have happened

Happened to me once

I was driving a fully loaded artic - 44 tonnes down the M6

The wheel on the trailer middle axle blew as I was overtaking another truck at 56 Mph
It ripped the mudguards off the trailer smashed the body work and anything that was attached to the trailer (It was bulk plastic so I had pipes etc and indicators)
They smashed into a Saab who was overtaking me and smashed his front end to buggery
He managed to keep hold of if as did I
The police had to shut the motorway to clear up the debris

It went off with some force and could have killed the guy in the Saab if he had spun out at 70 mph


Remember as a young MT driver sitting holding the split rims on a Bedford with my feet as I blew a tyre up on a 4 tonner
I remember a "senior" SAC looking bemused when a fitter pointed out there was a cage designed for that which would stop the rims taking that LAC's head off if they blew
Always used it after that

 

[wgaf]

She went out with a bang!...........


I'll get me coat.

 

[fat lazy techie]

We have a nice little powerpoint slideshow that shows some spam getting really badly fecked due to compressed gas and a hose blow out. May try and put some of the piccys on here next week when I'm back to work.

 

[MontyPlumbs]

We have a nice little powerpoint slideshow that shows some spam getting really badly fecked due to compressed gas and a hose blow out. May try and put some of the piccys on here next week when I'm back to work.

Is that the one with the guy split in half under a houtchin and he's wearing white socks?


Ahh...happy days.

 

[norfolkred1]

If it's the same one, they show it on the Risk Assesment course at Halton, and a fine mess it was as well

 

[Shugster]

I have formed a theory about this accident...

The tyre was damaged quite badly but didn't pop. Once it was removed it was no longer exposed to the stresses of the road but...

The outside air temperature might have been around 5 or 10°C, once she got in to the car with the heater on it could quite easily be 20°C or more.

Maybe this temperature difference was enough to cause the pressure to rise sufficiently to pop the tyre?

 

[Rocket_Ronster]

I suspect it would have been warmer while fitted, what with rolling friction and proximity to the brake discs.

 

[Shugster]

I suspect it would have been warmer while fitted, what with rolling friction and proximity to the brake discs.

It's got a shed load of cold air flowing over it, the heating effect from the brakes would be negligable compared to the cooling effects of the air.

 

[MontyPlumbs]

It's got a shed load of cold air flowing over it, the heating effect from the brakes would be negligable compared to the cooling effects of the air.

Having felt the warmth of my tyres after a trip, I'm inclined to believe they get hotter on the car than carried in it mate! DT_Xtremez_14:

 

[fat lazy techie]

Is that the one with the guy split in half under a houtchin and he's wearing white socks?


Ahh...happy days.

Yes that's the one. He's even got his hand in his pocket as well, the gash tw@t.

 

[Joe_90]

Perhaps if he'd kept his finger on the hole in the hose he'd have been fine?DT_Xtremez_42: