API 570 Study Guide (Full)

Pressure applied inside a pipe creates stress in the pipe wall. These stresses are highest on which weld orientation? - Answer- longitudinal weld Per B31.3, how much RT is conducted on circumferential welds of a pipe in normal service? - Answer- 10% for welded pipe, the normal thickness of under-tolerance is? - Answer- .010 or 10 mils The corrosiveness of soils can be determined by measuring the soils: - Answer- Resistivity when qualifying a weld procedure the essential variables must: - Answer- be recorded on both the WPS & PQR In severe refinery services which type of pipe is normally used? - Answer- seamless pipe a pipe has a thickness designation of "40S". what does the "S" mean? - Answer- Stainless steel Generally socket-welded pipe is not used for nominal pipe sizes above: - Answer- 2 inches A propane piping system should be classified as? - Answer- Class 1 According to ASME/ANSI B16.5 flanges from plate materials can only be used for: - Answer- Blind flanges Preheat should never be substituted for PWHT if: - Answer- the PWHT was used to prevent environmental cracking. During welding, non-esential variables: - Answer- Must be recorded only on the WPS and must be followed by the welder. During a hydrotest, all joints should be: - Answer- left uninsulated ASME/ANSI B16.5 requires flanges to be: - Answer- marked with the class rating. Graphitization of carbon steels begins to occur when metal temperatures exceed: - Answer- 800°F Dur