We have carried out destructive tests, this to explore the relation between the size of the ball
(the pressure of the ball) and its strength at given temperatures.
We have used an ambient temperature outside
the funnel of 35 degrees Celsius as measuring level.
At this tempature the inflation of the ball will give problems.
The ball will increase because the heat inside, especially with this temperature.
Increasing of the ball will result in deflating.
Inflate the ball to a diameter of 520mm / 20,5 inch and there will be no problem.
This corresponds with a pressure of around 0,05 to 0,1 bar.