Clean It Up

UK Window Cleaning Forum => Window Cleaning Forum => Topic started by: Sunshine Cleaning on March 19, 2007, 07:51:00 pm

Title: Kinetic Energy (Or How Hard Will The Tank Hit My Head)
Post by: Sunshine Cleaning on March 19, 2007, 07:51:00 pm

Just done some research on how secure our tanks need to be.

A vehicle travelling 40 mph hitting stationary vehicle.

250L tank becomes 8.1 Tonnes of mass, that means that if it is secured at 4 pionts on the van each point has to take 2.025 tonnes pressure.

The larger the tank the greater the impact value.

400L becomes 12.96 tonnes

600L becomes 19.44 tonnes

1000L becomes 32.40 tonnes

I have seen pictures on here where people have used what appear to be 1 tonne rachet straps connected at 2 points.

I have even read of people securing it on the van floor!!

Even the smallest tank needs something that can cope with 4 tonnes of pressure!

Security is only as good as your weakest point!

Title: Re: Kinetic Energy (Or How Hard Will The Tank Hit My Head)
Post by: Tosh on March 19, 2007, 08:10:38 pm

Is there such an animal as a ten-tonne rachet strap?

I'm sure there is; I may even have used them in my younger days!

Would four of them suffice; somehow cleverly fixed to the vehicle chassis?

How do lorries secure massive loads?

Title: Re: Kinetic Energy (Or How Hard Will The Tank Hit My Head)
Post by: poleman on March 19, 2007, 09:13:25 pm

http://www.omnipoleshop.com/2.0.van_crash.html

Title: Re: Kinetic Energy (Or How Hard Will The Tank Hit My Head)
Post by: JM123 on March 19, 2007, 10:42:13 pm

Having neither the will power or time or energy to check your calculations I'll accept them, there are numerous factors to consider though, its not as simple as whether your anchor points and harness can take the load applied but also
*what direction the load is being applied (this isn't straight forward as in an accident the load can be applied in cyclic motion or in 2/3 planes at varying angles
*what shear factors are introduced at each load point, can the material handle it?
*Where is the absorbed kinetic energy of impact being absorbed into?

There are even more factors involved but these are the main problem areas.

The simplest way to engineer a solution is to double up on values - ISO standards for structural designs is max 49% - that is the anticipated load of lets say a bridge should be a maximum of its calculated capacity.

Title: Re: Kinetic Energy (Or How Hard Will The Tank Hit My Head)
Post by: steve m on March 20, 2007, 11:03:12 am

after getting rid of the glazed eyes, no, they dont do 10 tonne staps. for that you would have to get chains. the largest straps they do is 4 tonne

Title: Re: Kinetic Energy (Or How Hard Will The Tank Hit My Head)
Post by: JM123 on March 20, 2007, 11:24:32 am

A local supplier sells 7.5tonne ratchet straps.