The capability and performance indices of the process were obtained from 3,620 measurements of the test pressure
per shift, with total of 10,680 values of the indication of pressure in the general data set, based on the 10 replicates in the three shifts of the tests (morning, afternoon and evening), considering 362 indications of pressure obtained per replicate.
As indicated in the introduction, the Hasan error is the value obtained by subtracting the test pressure
drop from the calculating pressure drop of the Hasan model.
These early experiences taught the team how sensitive every opening was and that even one small penetration could cause a plenum to not meet the required test pressure
. Plenums that were below the required test pressure
received immediate remediation to achieve passing results.
A practical limit to the test pressure
is about 75 Pa because above that test pressure
, door fan power must be substantially increased, and the risk of damage due to higher test fan wind velocities, and test pressures
ASME B 31.8 specifies the test pressure
factors for pipelines operating at hoop stress of [greater than or equal to]30% of SMYS.
To explain, the pipeline is hydrostatically tested to 1.5 x MOP and the valves must be cycled to the 1/2 closed position to equalize the high test pressure
within the valve body cavity.