Think think again, heres a list below:
Careful with that Axe Eugene - Ummagumma
Interstellar overdrive - piper at the gates of dawn
One of these days - Meddle
Cluster 1 - Division Bell
Signs of life - Momentary Lapse of Reason
Terminal Frost - as above
Any Colour You Like - DSOTM
Atom Heart Mother- Atom Heart Mother
A Saucerful of Secrets- A Saucerful of Secrets
On The Run- DSOTM
Marooned off the division bell is the best instrumental in the world.