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Tyres with run-flat properties > < Rising tyre temperature caused by insufficient tyre inflation pressure

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Tyre damage due to fitting error (fitting damage)
Tyre damage due to fitting error (fitting damage)
Bead core broken during tyre inflation.
   
Modern radial tyres for passenger cars are mounted only on safety rims. Safety rims have a hump -1- running along the bead seat.
1 - Hump (double hump H 2), extended double hump (EH2)
2 - Wheel rim flange
3 - Inner rim shoulder (e.g. tapered rim shoulder)
4 - Rim
5 - Wheel
6 - Well
7 - Outer rim shoulder (e.g. tapered rim shoulder)
The hump prevents the tyre from being pressed out of the rim shoulder during travel with insufficient tyre pressure.
When the tyre is inflated, the bead of the tyre may not slip completely over the outer rim hump.
In this case, there is a danger of the bead core becoming overstretched if the tyre pressure is too high. The steel wires would then rupture partially or completely. A broken bead core cannot be detected from the outside.
Special requirements for tyres with run-flat properties
Wheel rims with a raised double hump (Extended Hump EH2) are prescribed for tyres with run-flat properties (reinforced side walls) → Chapter. The raised double hump prevents the deflated tyre from slipping off its seat on the wheel rim when the tyre is run deflated.
  Note
To avoid damage, always observe the notes/instructions when fitting/removing tyres with run-flat properties → Running gear, axles, steering; Rep. gr.44.
  WARNING
t  Tyres with damaged bead cores are not seated safely and securely on the rim. Such tyres are a safety risk!
t  In addition, there is a risk of the partly broken bead core breaking apart during continued operation and the tyre could suddenly tear open. If the bead core breaks during inflation, the carcass will also be destroyed.
  N44-10214
Tyre with broken bead core and destroyed carcass
The figure shows a tyre with a broken bead core and destroyed carcass as a result of excess pulling force during fitting.
Bead damage due to faulty or incorrect tyre fitting with tyre-fitting machine
The following errors, which may occur when tyres are fitted, can lead to severe tyre damage:
t  If the opposite tyre bead is not seated completely in the rim well when the upper bead is rolled in on the tyre fitting machine. → Anchor.
t  If the fitting head is improperly adjusted.
t  If the edge of the fitting roller rolls onto the bead.
t  If the guide rollers are worn or have sharp edges.
  N44-10238
If the tyre bead is split.
In these cases, the bead, which is under great tension, can be cut into in the direction of rotation, split and/or be pinched off down to the core wire.
It is often possible to identify the tracks of the guide roller as it was applied or ran off where the damage occurred.
  Note
Both tyre beads as well as the rim shoulders must always be coated with assembly paste.
If fitting damage remains undetected, there is a danger that the tyre will fail later during operation.
THEREFORE!
t  Never fit a tyre without using assembly paste.
t  Do not allow the bead seating pressure to exceed 3 bar.
t  Do not allow the tyre inflation pressure to exceed 4 bar.
t  When the tyre has been fitted, reduce the tyre pressure to the specified value.
  N44-10239

Tyres with run-flat properties > < Rising tyre temperature caused by insufficient tyre inflation pressure