Not sure if this is of any interest to anybody but have got alot of useful info from this site this might help somebody.
One of our guys was given the wrong key to one of our Ingersol locks,
He forced the key into the key way and yes you guessed broke it of. How he got it in so far I do not know.
I was lucky who ever had been there prior had not dead locked the door(great one of the most secure locks not locked properley) I opened with a screw driver.
I tried to get the broken key out from the front but it was jammed solid, because the door was open I was able to strip the lock down. From the looks of the cylinder I would say this type of lock was unpickable.
10 levers hinged side bar. Any way the only way I could see to attack the broken key was from the back of the cylinder with a punch and a hammer.
I released all ten springs on the levers and tapped the key out. Wow it was jammed but came out, pushed all the springs back re-assembled job done.
Was just as well as didn't have a replacement and would not have been able to secure the door.
I was very lucky as I got the door open, What would I have done if the door was locked?
Drill would have been the only way and then I would have needed at least a new cylinder to secure the door.
scifibuff