Dear folks,i'd like to ask your opinion. recently i did some hydrostatic pressure test for wellhead equipment and record it under pressure chart (barton chart).the graph were taken had a very slightly drop which drive me to think about allowable pressure drop tolerance.i'm confused about what is acceptable and what is not acceptable when i look at those chart result.As i look at API 6A, it doesn't mention 'allowable pressure drop' to qualify accepted test result.API 6A on annex F.1.1.10 b) about hold period mention:"Pressure shall be considered stabilized when the rate of change is no more than 5 % of the test pressure per houror 3,45 MPa/h (500 psi/h), whichever is less. Pressure shall remain within 5 % of the test pressure or within3,45 MPa (500 psi), whichever is less, during the hold period."on the other hand, API 6A annex F.1.6.3 about pressure integrity mention:"The hydrostatic test at room temperature is passed if no visible leakage occurs during the specified pressure holdperio...
