Fabrication and welding of SA 387 GRADE 11 CLASS 2 MATERIALS 3

[amsomu04]

Hello all,

Recently we got an order to manufacture the reacter vessel . Material Sa 387 Grade 11 class 2. Manufacturing code as per ASME Sec 8 Div.1. Request all to give suitable welding consumable, preheat and post weld HT requirements of this material. Thickness of the plate 12mm.
Thank you all in advance.

 

[DVWE]

The best advice I can give you is to hire a competent welding engineer or welding specialist.

If your company cannot afford one, they should not bid on fabrication of unfamiliar materials, and you should look for a new job.

The devil is in the details; she also wears prada.

 

Ditto.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[weldstan]

Sales will often bid on a project with $$ in their heads without contemplation of risks to actually achieving those $$.
Your company will need to hire a consultant to assist in fulfilling the contract. Welding procedures will have to be qualified. Section VIII gives requirements/guidelines as to PWHT and preheat.

 

[weldstan]

I don't quite know how that initial sentence came out that way but it should have read, "...with dollar signs in their heads without contemplation of risks to actually achieving those dollars."

 

[SnTMan]

But, but, but if we priced all that in, we'd never get the job...

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[weldstan]

A star for you SnTMan.
I've seen more than one vessel manufacturer that went under when Sales oversold the company's ability to deliver the product(s).

 

[SnTMan]

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[amsomu04]

Hello all,

Based on review of technical articles I choosed ER80SB2 and E8018B2 with preheating of 160 Deg C. As per UCS 56 less than 16mm no need of PWHT. Not yet did the PQR since the vessel is in design stage.

My question is am I choosed the correct electode. Or I need to choose Er70sB2L to use the vessel As welded condition..

Request all your suggestions..

 

[kiad]

please be noted pwht is required. see UCS-56 Note (a) for P No.4.

 

[amsomu04]

Seen the Code UCS-56 Note (b)1,2,3 says PWHT not manditory when meeting the following conditions.

I.e, Thk.16mm Max, Carbon Max .015 and Preheat 120Deg C. Oue Base metal Thick is 12mm.

GENERAL NOTES:
(a) Except for exemptions in General Note (b), postweld heat treatment is mandatory under the following conditions:
(1) on material of all thicknesses if required by UW-2;
(2) on all other P‐No. 4 Gr. Nos. 1 and 2 materials.
[highlight #FCE94F](b) Postweld heat treatment is not mandatory under the conditions specified below:
(1) for circumferential butt welds in pipe or tube of P‐No. 4 materials where the pipe or tubes comply with all of the following
conditions:
(a) a maximum nominal thickness of 5/8 in. (16 mm);
(b) a maximum specified carbon content of not more than 0.15% (SA material specification carbon content, except when further
limited by the purchaser to a value within the specification limits);
(c) a minimum preheat of 250°F (120°C).[/color][/highlight]
(2) for P‐No. 4 pipe or tube materials meeting the requirements of (1)(a) and (1)(b) above, having nonpressure attachments fillet
welded to them, provided:
(a) the fillet welds have a maximum throat thickness of 1/2 in. (13 mm);
(b) a minimum preheat temperature of 250°F (120°C) is applied.
(3) for P‐No. 4 pipe or tube materials meeting the requirements of (1)(a) and (1)(b) above, having studs welded to them, a minimum
preheat temperature of 250°F (120°C) is applied.
(4) for P‐No. 4 pipe or tube materials meeting the requirements of (1)(a) and (1)(b) above, having extended heat absorbing fins electrically
resistance welded to them, provided:
(a) the fins have a maximum thickness of 1/8 in. (3 mm);
(b) prior to using the welding procedure, the Manufacturer shall demonstrate that the heat‐affected zone does not encroach upon the
minimum pipe or tube wall thickness.
(5) for tubes or pressure-retaining handhole and inspection plugs or fittings that are secured by mechanical means (tube expansion,
shoulder construction, machine threads, etc.) and seal welded, provided the seal weld has a throat thickness of 3/8 in. (10 mm) or less, and
preheat to a minimum temperature of 250°F (120°C) is applied when the thickness of either part exceeds 5/8 in. (16 mm).

 

[amsomu04]

If we meet these conditions as per UCS 56 P.No.4 Note (b)1,2,3 can we neglect the PWHT. If we do the PQR to be passed without PWHT can proceed the job without PWHT.

 

[kiad]

UCS-56 (b) talks about circ. butt weld Of pipe or tube. You mentioned 12 mm thickness plate!.

 

[DVWE]

(1) for circumferential butt welds in [highlight #FCE94F]pipe or tube[/highlight] of P‐No. 4

The devil is in the details; she also wears prada.

 

kiad is correct; in my 2010 & 2017 editions I see no mention of PWHT exemption for P-no.4 plate. General note (a)(1) is quite clear.
In situations where there is exemption, welding technique and controlled heat input are important aspects to successfully welding the Cr-Mo steels. These alloys must be approached with caution and an understanding of their behaviour.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[amsomu04]

Thank you all for your responses.

(a) Except for exemptions in General Note (b), postweld heat treatment is mandatory under the following conditions:

Please clarify the point (a). Except for exemptions in general note (b) PWHT is mandate for P4.

So I thought that according to Note (b) I can neglect the PWHT Provided meeting the thickness limit, carbon level and preheating requirements.

This is actually a reactor works in elevated temperature at low pressure. Plates have to be joined with LS weld also CS welding involved on this. The size of the equipment is around 6 meter long and 4 meter height and 2 meter breath also having more stiffeners. Which is very difficult to PWHT of joints.Your suggestions are invited to neglect pwht due to feasibility. And any alternative ways...Thanks in advance..

 

[DVWE]

This is actually a reactor works in elevated temperature at low pressure. Plates have to be joined with LS weld also CS welding involved on this. The size of the equipment is around 6 meter long and 4 meter height and 2 meter breath also having more stiffeners. Which is very difficult to PWHT of joints.Your suggestions are invited to neglect pwht due to feasibility. And any alternative ways...

All the more reason for you to hire or contract the services of a competent welding engineer or welding specialist.

The devil is in the details; she also wears prada.

 

[amsomu04]

I taken all your advices to contract a welding experts.
Meanwhile please let clarify what is wrong in my selection of electrodes, code exemptions of PWHT etc. will help me more,
Thank you..

 

[david339933]

Ok,
ER80S-B2 and E8018-B2 are normally acceptable choices for P4 material.
Check out APP. R in Sec. VIII Div. 1 for preheat temps.
If you are building a vessel...there must be a long seam?..yes?. Exemption is only for circ. seams in pipe per General Note (2)(b)(1) you quoted above.

 

[amsomu04]

Dear David339933,

Thank you for your reply.

Our Vessel [highlight #FCE94F](Operating Pressure 0.1Kg/Sq.cm)[/highlight] don't have Long seam and Cir seam weld. It is actually a Rectangle vessel with Corner Joints and Fillet weld only. Suggested by our Welding Engineer to use ER80S-B2 with [highlight #FCE94F]Min.200 Deg Preheat without PWHT[/highlight]. All around the vessels provided stiffeners with Fillet Weld. Size of the Fillet Less than 12mm. I hope the Filler selections is fine. My question here is Since NO PWHT involved, Why don;t we go with ER70S B2L instead of ER80S-B2. Requested your thoughts here..