A STUDY OF THE CORRELATION FACTOR BETWEEN FULL-SCALE AND S4 RAPID CRACK PROPAGATION (RCP) TESTING IN GAS PIPING APPLICATIONS

摘要

This paper will show that the current ISO correlation factor between S4 testing and Full- Scale (FS) RCP testing is very conservative, based on our results of North American PE2406/2708 and PE3408/3608 polyethylene pipes that were tested. This paper will present actual test data using both the S4 and FS test methods and compare these data to predictions based on the current S4-to-FS conversion equation per the governing ISO standards. Based on the measured P_(cFS)and P_(cS4) data, we estimated the Maximum Operating Pressures (MOP) and observed that the MOP based on RCP constraints exceeded the MOP based on design and pressure ratings. These results suggest, therefore, that the current polyethylene piping products in the gas distribution market have very good RCP performance.