2002 Mercury Cougar Gone through 2 clutches done by trans s

Have had the clutch replaced twice and after a couple of weeks seems to act and basically go out again. The clutch disc seems to come apart, any ideas of what could cause this. I don't speed shift nor do anything else that would cause this that i know of????? The trans shop even put in a heavy duty clutch he says. The flywheel dosn't have hot spots it either???????????