tube killer!
I've done that a couple of times (which really sucks when it happens of course). Watch out that you don't stress the pin/glass connections by handling a tube too roughly or forcing it in a socket (esp. a stiff tight socket like some Russian or maybe Chinese ones). And I would not use pin straighteners because they seem too hard on the tube button base. Remember they are
glass...
p.s. if you ever have to straighten the pins do them very carefully one at a time with a hollowed out pen or maybe pliers.