comparing UT acceptance ASME VIII, B31.1 and B31.3

Dear Colleagues,

After comparing the acceptance criteria from these 3 codes it seems like the acceptance for B31.3 is much less stringent then for the other two codes.

Is this correct and does anbody know why this is? Or am I just overlooking something in B31.3?

The acceptance for ASME VIII and B31.1 seem to be exactly the same. They don't allow linear discontinuities over 20% DAC and reject rounded discontinuities when they exceed a certain length and 100%DAC.

As far as I can find; B31.3 does not reject rounded discontinuties. And linear discontinuties are allowed to have some length and are allowed to produce indications up to 100% DAC (similar as is allowed for the rounded indications in VIII and B31.1).

06:05 Apr-02-2008 bob sudharmin Engineering, Reliability and Integrity Eng Shell Malaysia Trading, Malaysia, Joined Jan 2008 ^{54}

Re: comparing UT acceptance ASME VIII, B31.1 and B31.3 Acceptance criteria does not necessarily be the same when comparison is being made against different code requirements. ASME Viii is a pressure vessel code, B31.1 - Power Piping and B31.3 - Process Piping. It is true that B31.3 is less stringent but then again take note it is a piping system designed for and above 0 but less than 105Kpa (15psi)

----------- Start Original Message ----------- : Dear Colleagues, : After comparing the acceptance criteria from these 3 codes it seems like the acceptance for B31.3 is much less stringent then for the other two codes. : Is this correct and does anbody know why this is? Or am I just overlooking something in B31.3? : The acceptance for ASME VIII and B31.1 seem to be exactly the same. They don't allow linear discontinuities over 20% DAC and reject rounded discontinuities when they exceed a certain length and 100%DAC. : As far as I can find; B31.3 does not reject rounded discontinuties. And linear discontinuties are allowed to have some length and are allowed to produce indications up to 100% DAC (similar as is allowed for the rounded indications in VIII and B31.1). : Looking forward to an explanation. : Kind Regards, : Jarno de Jonge ------------ End Original Message ------------

Re: comparing UT acceptance ASME VIII, B31.1 and B31.3 Quote "It is true that B31.3 is less stringent but then again take note it is a piping system designed for and above 0 but less than 105Kpa (15psi)"

Mr. Sudharmin, this is not correct. 31.3 most certanly allows for pressures above 15psi.

Regards,

RB

----------- Start Original Message ----------- : : Acceptance criteria does not necessarily be the same when comparison is being made against different code requirements. : ASME Viii is a pressure vessel code, B31.1 - Power Piping and B31.3 - Process Piping. : It is true that B31.3 is less stringent but then again take note it is a piping system designed for and above 0 but less than 105Kpa (15psi) : : Dear Colleagues, : : After comparing the acceptance criteria from these 3 codes it seems like the acceptance for B31.3 is much less stringent then for the other two codes. : : Is this correct and does anbody know why this is? Or am I just overlooking something in B31.3? : : The acceptance for ASME VIII and B31.1 seem to be exactly the same. They don't allow linear discontinuities over 20% DAC and reject rounded discontinuities when they exceed a certain length and 100%DAC. : : As far as I can find; B31.3 does not reject rounded discontinuties. And linear discontinuties are allowed to have some length and are allowed to produce indications up to 100% DAC (similar as is allowed for the rounded indications in VIII and B31.1). : : Looking forward to an explanation. : : Kind Regards, : : Jarno de Jonge ------------ End Original Message ------------

Re: comparing UT acceptance ASME VIII, B31.1 and B31.3 There seems to be only an exclusion in B31.3 for this pressure range under certain circumstances. This means that we are just as well talking about pressurised piping.

For this reason I found it remarkable that the acceptance is less stringent for B31.3 piping than for other pressure containing parts (vessels and B31.1 piping)

Jarno

----------- Start Original Message ----------- : Quote "It is true that B31.3 is less stringent but then again take note it is a piping system designed for and above 0 but less than 105Kpa (15psi)" : Mr. Sudharmin, this is not correct. 31.3 most certanly allows for pressures above 15psi. : Regards, : RB : : : : Acceptance criteria does not necessarily be the same when comparison is being made against different code requirements. : : ASME Viii is a pressure vessel code, B31.1 - Power Piping and B31.3 - Process Piping. : : It is true that B31.3 is less stringent but then again take note it is a piping system designed for and above 0 but less than105Kpa (15psi) : : : Dear Colleagues, : : : After comparing the acceptance criteria from these 3 codes it seems like the acceptance for B31.3 is much less stringent then for the other two codes. : : : Is this correct and does anbody know why this is? Or am I just overlooking something in B31.3? : : : The acceptance for ASME VIII and B31.1 seem to be exactly the same. They don't allow linear discontinuities over 20% DAC and reject rounded discontinuities when they exceed a certain length and 100%DAC. : : : As far as I can find; B31.3 does not reject rounded discontinuties. And linear discontinuties are allowed to have some length and are allowed to produce indications up to 100% DAC (similar as is allowed for the rounded indications in VIII and B31.1). : : : Looking forward to an explanation. : : : Kind Regards, : : : Jarno de Jonge ------------ End Original Message ------------

05:33 Apr-03-2008 bob sudharmin Engineering, Reliability and Integrity Eng Shell Malaysia Trading, Malaysia, Joined Jan 2008 ^{54}

Re: comparing UT acceptance ASME VIII, B31.1 and B31.3 My sincere apologies for the inadvertent mistake. I must have overlooked the fact that the statement was meant to be an exclusion of the code's scope. Thank you for the comment.

----------- Start Original Message ----------- : Quote "It is true that B31.3 is less stringent but then again take note it is a piping system designed for and above 0 but less than 105Kpa (15psi)" : Mr. Sudharmin, this is not correct. 31.3 most certanly allows for pressures above 15psi. : Regards, : RB : : : : Acceptance criteria does not necessarily be the same when comparison is being made against different code requirements. : : ASME Viii is a pressure vessel code, B31.1 - Power Piping and B31.3 - Process Piping. : : It is true that B31.3 is less stringent but then again take note it is a piping system designed for and above 0 but less than 105Kpa (15psi) : : : Dear Colleagues, : : : After comparing the acceptance criteria from these 3 codes it seems like the acceptance for B31.3 is much less stringent then for the other two codes. : : : Is this correct and does anbody know why this is? Or am I just overlooking something in B31.3? : : : The acceptance for ASME VIII and B31.1 seem to be exactly the same. They don't allow linear discontinuities over 20% DAC and reject rounded discontinuities when they exceed a certain length and 100%DAC. : : : As far as I can find; B31.3 does not reject rounded discontinuties. And linear discontinuties are allowed to have some length and are allowed to produce indications up to 100% DAC (similar as is allowed for the rounded indications in VIII and B31.1). : : : Looking forward to an explanation. : : : Kind Regards, : : : Jarno de Jonge ------------ End Original Message ------------