I want to use API 5L Gr.B Seamless in place of ASTM A106 Gr.B 2

[Sabirhussain]

Dear Freinds,

I want to use API 5L Gr.B Seamless in place of ASTM A106 Gr.B.
Please tell me detail for this replacements Sabir Hussain
Sr.Engineer Piping
J-Tech Pvt Ltd
Lahore Pakistan

 

[gunnarhole]

Sabirhussein,

If we are talking about an ASME VIII pressure vessel, API 5L is not listed as an approved material in ASME Section II.

If, however, you are designing a piping system per ASME B31.3/4/8 then you can use API 5L materials. As in any design you must assure yourself that the mechanical and physical properties of the grade you select are appropriate for the service you are designing for.

Regards,

Gunnar

 

[Merzi]

Sabir,

Now a days you can get dual certified MTR for pipes. Majority of the mills will certify the pipes to SA 106 Gr B/ SA 53 / API 5L Gr B.

Regards

Merzi

 

[gunnarhole]

Sabir,

Merzi makes a good point. In a different application we have found that dual certified 316/316L flanges are useful in that they allow us to use the higher allowable ratings (per ASME B16.5) of the 316 and still get the low carbon content required by the welding process.

Gunnar

 

[AZ314]

BOTH 5L GRADE B & A106 GRADE B HAVE THE SAME SMYS = 35000 PSI , BUT A 106 IS RECOMENDED FOR HIGH TEMP , SERVICES & 5L IS ONLY USED FOR NORMAL TEMP. SERVICES

 

[bmoorthy]

Simply API 5l Gr B certified pipe cannot be used in place of SA 106 Gr B in a pressure vessel or o heatexchanger designed to ASME and especially U stamp job, Specifically if it is going to US. If the job is going to be some where in Pakisthan then you could be using ASME sec VIII as design standard and this may not have the force of LAW, hence use of API 5l Gr B in place of A 106 Gr B is based on your engineering judgement (Fitness of purpose) in most of the less critical services this substitution would do no harm but again you have to decide which is critical and which is not.

The allowable stress for API 5L is given in ANSI B 31.3. You may jolly well substitute the grades in Pressure plant piping.

As it has been pointed out multiply marked pipes are acceptable for use in ASME vessels and exchangers.

However there are some salient difference between API 5L gr B and SA 106 Gr B. Compare the chemistry which need to be reported in case of API and A 106. Also API pipes are ordered to OD (From the year 2000 ) where as SA 106 are ordered to NPS.

How does it matter?

Take for example, if you order the pipe as API 5L Gr B 4" (Thickness specified) then the supplier would supply 4" OD pipe instead of 114.3mm pipe.

In case of API you may have to specify PSL 1 or 2, based on criticallity of service.