PRE ò PREN

PREN = % Cr + 3.3%Mo + 16%N

CALCULATION OF THE PITTING RESISTANCE CORROSION (PRE)

INTRODUCTION

PRE formula is used to compare the resistance to pitting corrosion (pitting) of
varioustypes of stainless steels, and is based onthe chemical composition ofthese.


PREN numbers (or PRE) are useful for sorting andcomparison of the different
steel, but can be used topredict whether aparticular steelissuitable for
given application,wherepittingcan be a hazard.
Actualor range specifiedcompositionscan be used andusually involve
chromium, molybdenum andnitrogenin the calculation, although other formulas in the
marketwhere they useother percentagesand evenaddotheralloying elements such as
Tungsten, also known as tungsten (W).

PREN = %Cr + 3,3 ( %Mo + 0,5 · %W ) + 16 · %N

PREN = % Cr + 3.3%Mo + 16%N

Aproximate data for information purposes