V6 AKE exhaust pipes to turbocharger

I've now sent three turbochargers for overhaul after the technical inspection (STK). Every time, the same message would come back:

Total economic loss. Turbine shaft seized. Structural damage to the blades caused by foreign objects.

After a lot of back and forth, I finally called Garrett directly. They told me that, in principle, it is not permitted to repair VTG loaders.

When I confronted STK about this, I was told that while what would be correct, they lacked the necessary expertise to perform such repairs, but they could carry them out within a very limited scope. The structural damage to the impeller blades is caused by abrasion of the 'expansion tubes' located between the cylinder exhaust and the turbocharger. This abrasion is often caused by wear or excessively high exhaust temperatures, for example, in vehicles that have been 'chipped' (modified for performance).

Is there a way to improve this?

Dieselmike wrote:

Is there a possibility for improvement in this regard?

As far as I know, in that case, you have to replace the exhaust manifolds. Small rust particles detach and then damage the turbine on the exhaust side.

Yes, mufflers and compensators. There's a TPL (Technical Product Literature) available for them. Not cheap.

I inquired with Audi about this. According to their technical specifications, in the event of a turbocharger failure, the exhaust manifold and compensators should be replaced. Audi is covering a portion of the costs as a goodwill gesture. There has been a new, 'improved' series of compensators since 2002.
Left compensator: 059 131 789 G, €59.90.
Compensator, right side: 059 131 789 D, 59.90 Euros.
Krümmer: 059 253 033 M, €161.84