HI Vamsi,
in the node SPRO: FSCM-> TRM-> TRansaction Manager -> Foreign Exchange -> Transaction Management -> TRansaction Types -> Assign Forex attributes
for your product type and transaction type, check the checkbox Transl. to Lc.
BY doing this the system will treat the transaction spot rate as the basis for translation and no profit/loss flow will be generated.
REgards,
NIkhil