Hello
I have some clam coins in my poleniex acoount, i just need to withdraw .
How can i can exchange clam coins to my bitcoin wallet?
This is weird. Your clam coins are already on a trading exchange and you have problems in converting them to Bitcoins?

What prevents you from just selling them on the exchange for bitcoins and then withdrawing bitcoins?
Well, already it's in the account. So just a selling order need to be generated. Within certain time you'll get the value of what you had in terms of bitcoin. Now you could withdraw the bitcoin to whatever the wallet you wish to make. Rather than this you won't be finding any solution for this. Else find a trader who is ready to accept clam and provide you with bitcoin.