Wednesday, August 11, 2010

Re: Re: [MW:6431] RE: 6343] HARDNESS ON SS WELDING

Dear Shrinivas

One factor could be interpass temperature, I think more layers will require more heat hence it will reduce the hardness of the metal.

As Mr. John said, Reduce heat input (interpass temperature) & also try method told by Mr. Jaspal Singh. Very sure it's better than applying more layers.

Regards
Manpreet Singh
Welding Engineer
Spiecapag






On Tue, 10 Aug 2010 09:39:52 +0530 wrote
>Dear John,
We have already tried two layers, but then the hardness is only 45RC, there is no problem in thehard facingelectrode as we have tested it in a separate pad it is giving 60 RC. One of our group professional has suggested the followingprocess,I layer 7018next 309 one layer, then we have to grind the half bead of 309 deposit, then again one more layer 309, grind the half bead,finally the hard facing layer, intension is to reduce the dilution.
Please given your comments on this
Srinivas

--- On Mon, 9/8/10, John Du Plessis wrote:

From: John Du Plessis

Subject: [MW:6403] RE: 6343] HARDNESS ON SS WELDING
To: materials-welding@googlegroups.com
Date: Monday, 9 August, 2010, 9:38 PM





























The loss or reduction in hardness is
purely because of dilution. The only way to overcome the issue is to minimize
the dilution. Reduce the heat input to ass low as possible on the first layer
of the hardfacing. Normally a single pass will never achieve the hardness
required and ths yu will have to weld at least two passes.



It is fairly easy to assume the amount of
dilution and calculate how many weld passes must be deposited to achieve the
minimum hardness



John
du Plessis

Technology Manager



Tel: +27 (11) 298 2100

Tel: +27 (11) 298 2103
(Direct)

Fax: +27 (11) 836 6014

Mobile:+27 (0) 82 883 4970

www.saiw.co.za



This email and any
files transmitted with it are confidential and may be legally privileged. They
are intended solely for the use of the individual or entity to whom they are
addressed. Access to this e-mail by anyone else is unauthorised, and any
disclosure, copying, distribution or other use of this e-mail is prohibited and
may be unlawful. We will not under any circumstances have any responsibility or
liability arising out of or in connection with any unauthorised use of this
e-mail. If you have received this email in error please notify the sender
before deleting it.













From:
materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of gaddam Srinivas

Sent: 07 August 2010 04:23 AM

To: materials welding

Subject: [MW:6343] HARDNESS ON SS
WELDING











Dear Sir,





One layer MS electrode 7018 and 2 layers of SS-309
grade electrode is being used to fill the gaps, and finally hardfacing
electrode of 60 RC(appplication) fabricators of ID fans. They are using
the above combination to join MS plate to hardfaced wearplate, now the
problem is, the hardness of the hardfacing electrode when directly tested, it
is coming 60 RC and when it is used as a final layer on SS 309 grade
electrode it is coming 35 RC. They require the hardness of 60 RC but they
cannot change the process of using 7018 and 309 as it ismentioned in
the drawing. Now how can they get the 60 RC, whether they have to change the
welding sequence or any other solution plealse let me know.





Thanks & Best REgards


Srinivas







--

To post to this group, send email to materials-welding@googlegroups.com

To unsubscribe from this group, send email to
materials-welding-unsubscribe@googlegroups.com

For more options, visit this group's bolg at http://materials-welding.blogspot.com/

The views expressed/exchnaged in this group are members personel views and
meant for educational purposes only, Users must take their own decisions w.r.t.
applicable code/standard/contract documents.









--

To post to this group, send email to materials-welding@googlegroups.com

To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com

For more options, visit this group's bolg at http://materials-welding.blogspot.com/

The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.






--
>
To post to this group, send email to materials-welding@googlegroups.com
>
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
>
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
>
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
>

--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.

No comments:

[MW:34820] RE: 34813] Clarification in Rate of heating and cooling.

Hello,   Please see the response below.   Regards.   P. Goswami, P. Eng, IWE.   From: materials-welding@googlegroups.com <materials-weld...