'planchar' is equivalent to the English 'swipe' - i.e. the action of passing a credit card through the reader. In Chile, a 'planchazo' is the illegal swiping of the card twice (or more times) to extract extra payments for the same purchase.

http://www.mercuriovalpo.cl/prontus4_noticias/antialone.html...

BankBoston Corredora de Seguros -cuya venta de productos ha aumentado en un 100 por ciento en lo que va de este año respecto del mismo período del 2004- tiene el seguro "cuenta protegida", en que por 0,49 UF al mes, el asegurado protege sus cheques, sus tarjetas de crédito y débito, se cuida de fraudes por clonación, compras y pagos, tiene asistencia legal, tramitación de bloqueos, y evita el denominado "planchazo" (o adulteración de la banda e impresión múltiples de vales en establecimientos comerciales), etc.

Dyfed Powys Police | Cheque and Credit Card FraudCheque and Credit Card Fraud. To reduce the risk of you being the victim of fraud ... At some outlets your card may be swiped twice, this second swipe is to ...
www.dyfed-powys.police.uk/en/advice/fraud/creditcard/ - 9k - Cached - Similar pages

Swiping Back At Credit-Card FraudBogus transactions are falling overall, but e-tailers are still feeling the pain.
www.businessweek.com/magazine/content/05_28/b3942095_mz020.... - 58k - Cached - Similar pages

Beware cloned credit cardsSomeone, somewhere made an extra swipe of your credit card. ... As with any kind of credit card fraud, a consumer victim is not on the hook for the bill. ...
www.bankrate.com/brm/news/cc/20020524a.asp - Similar pages

Street-Level Credit Card Fraud - Security Fix


I can't find an equivalent 'slang' term in English, so I suggest the adequately descriptive 'multi-swipe' but suggest that in the translation you should omit the word 'denominado' because it's probably not called that in banking circles.