PREHEAT TEMPERATURE

[Manoj Mumbai]

Dear Experts,

The preheat temperature shall not be less than 55 deg. C as per QW-406.1 but  not specified a maximum how much it can be from the temperature noted in PQR as preheat temperature is minimum temperature and interpass temperature is the maximum temperature.

My question , Is there any limitation to increase preheat temperature than mentioned in PQR. suppose PQR temperature is Ambient, say 38 deg. C, can we increase preheat temperature to 204 deg. C.  I have a qualified procedure of P6 material at ambient temperature 38 deg.C now I have to include preheat temperature.

Thanks in advance for your expert opinion.

Manoj.

[Kannayeram Gnanapandithan]

Yes based on thickness

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-weld...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CACgUO5%3DH94mRN3EHOgHBCxM3%2BuEJp3uqYP6qOrOjVbzrD0_bxg%40mail.gmail.com.

[Gerry Lourens]

There are no limits to the Preheat temperature provided that there are no toughness requirements.

If toughness (impacts) are required :

the maximum inter-pass temperature qualified equals the maximum preheat temperature.

Best Regards,
	Gerry Lourens Welding Engineer New Age Engineering Solutions
	M: +27 62 192 1207 T:  +27 17 631 5282 F:  +27 (0)86 616 9701 E:  gerry....@newage-eng.com A:  3 York Street, Evander, 2280

--

[Kannayeram Gnanapandithan]

Could you give code ref for control of preheat on maximum side

To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAFgehWe%3DgfP78ODmmJBmWd%2B28HhfBD3Jtk5tC2SrYbt%2B7x0SGA%40mail.gmail.com.

[Manoj Mumbai]

ASME B31.3 and RP582

To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAJzm4eNv8zRKZ%2Bi-yZcPoKKGAGVOE4WfO_cztr3s8k4T5sXJtw%40mail.gmail.com.

[Ganesh Muthurajan]

Mr. Manoj, 

Preheat requirements for P6 materials ( martensite stainless Steel). 

As per ASME 31.3 Table  330.1.1

State  the minimum requirement are 200. Deg. C. For all thickness. There is no additional  requirement. We should follow min 200 deg C minimum temperature.  

Ans the inter pass temperature is min 315 deg  C, 

Even your PQR is in ambient temperature.  

--

[Prem Nautiyal]

Min and Max preheat temperatures are mentioned in ASME Sec II C also for certain consumables.

Regards

Prem Nautiyal 

To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CACgUO5mUfYrriofY2QSXT26TX%2BQ86CE513z8Uq1CSFcXQc3QqA%40mail.gmail.com.

[Kannayeram Gnanapandithan]

Preheat temp maximum restricted only in AWS D1.1 only

To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAM0EmFLvGVTmab%2BDW17v58hTdLe%3D9JN6oda%2BFsLHB6obY2xgCw%40mail.gmail.com.

[ramesh kumar]

Dear Manoj,

               Please also refer as mentioned in ASME SEC IX for your query.............

QW-406.3

PREHEAT

An increase of more than 55Deg C in the maximum interpass temperature recorded on the PQR. This variable does not apply when a WPS is qualified with a PWHT above the upper transformation temperature or when an austentic or P No. 10H material is solution annealed after welding.

--

[Kannayeram Gnanapandithan]

No where mention the restriction on maximum preheat temp as per mention code ASME B31.3, ref 330 and 330.2,,,  and API RP 582, 8 preheat and interpass temp.  Restriction on Max interpass tem only to avoid coarse grain that too for Impact requirements

THANKS & BEST REGARDS,

KG.PANDITHAN, BE, IWE,  CSWIP 3.1,

ISO 9712 Level 2 in VT,

ASNT-Level II in PT,MT,RT & UT,

LA ISO 9001-2015,

International Welding Engineer. 

CONSULTANT-WELDING & QUALITY

Mobile no: +919940739349

To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CACgUO5mUfYrriofY2QSXT26TX%2BQ86CE513z8Uq1CSFcXQc3QqA%40mail.gmail.com.

[Manoj Mumbai]

Dear team,

We got an order for 120 mm the carbon steel pressure vessel from our customer. Is there any special care to follow during fabrication. It will be very helpful if anybody could share a procedure for high wall thick pressure vessel fabrication. I have no experience of high wall thick PV fabrication.