Hi
All hardfacing deposits will show stress relief cracks after welding.
However one should be careful about the direction of cracks..
Transverse cracks are regular and must be present.
But linear cracks along the axis of weld are dangerous and can cause failure in further service...
It depends upon the client to accept or reject such linear cracks..
What welding process has been used on this ID fan blade for hardfacing?
To get hardness of 79HRc is it a deposit with Boron Carbides ?
Regards
Prem Nautiyal
On Sat, 06 Feb 2010 08:50:34 +0530 wrote
>Sethu,
its some time since I have been involved with hard facing. The hard
surfacing we used was designed to crack!!!!! The reason for this is that
the hardfacing is not used to bond material per se, it is used as
erosion / abrasion resistance only, the cracks actually relieve residual
stresses within the weld itself.
your contractor is probably right..........just check that the
hardfacing is in fact supposed to crack. The cracks will not affect the
wear resistance
Declan
On 05/02/2010 15:28, sethurama lingam wrote:
> Dears,
> I need some clarification in Hard facing in ID fan impeller ,But we
> are received with more cracks in linear,tranverse at the same time
> goes depth ,we are not able to measure it.
> Our contractor explained that cracks are normal in hard facing at 79
> RC hardness level.I think that it should be controlled at that time of
> hard facing.Any one send some acceptance criteria for hard facing, we
> are accepting that cracks it current level ,it will affect the
> impeller life .
>
> --
> Regards
>
> Sethu Ramalingam.P
> Sr.Engineer,
> ACPCPL
> --
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> 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.
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PREM S NAUTIYAL
CELL : 9820313278
--
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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.
All hardfacing deposits will show stress relief cracks after welding.
However one should be careful about the direction of cracks..
Transverse cracks are regular and must be present.
But linear cracks along the axis of weld are dangerous and can cause failure in further service...
It depends upon the client to accept or reject such linear cracks..
What welding process has been used on this ID fan blade for hardfacing?
To get hardness of 79HRc is it a deposit with Boron Carbides ?
Regards
Prem Nautiyal
On Sat, 06 Feb 2010 08:50:34 +0530 wrote
>Sethu,
its some time since I have been involved with hard facing. The hard
surfacing we used was designed to crack!!!!! The reason for this is that
the hardfacing is not used to bond material per se, it is used as
erosion / abrasion resistance only, the cracks actually relieve residual
stresses within the weld itself.
your contractor is probably right..........just check that the
hardfacing is in fact supposed to crack. The cracks will not affect the
wear resistance
Declan
On 05/02/2010 15:28, sethurama lingam wrote:
> Dears,
> I need some clarification in Hard facing in ID fan impeller ,But we
> are received with more cracks in linear,tranverse at the same time
> goes depth ,we are not able to measure it.
> Our contractor explained that cracks are normal in hard facing at 79
> RC hardness level.I think that it should be controlled at that time of
> hard facing.Any one send some acceptance criteria for hard facing, we
> are accepting that cracks it current level ,it will affect the
> impeller life .
>
> --
> Regards
>
> Sethu Ramalingam.P
> Sr.Engineer,
> ACPCPL
> --
> 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.
PREM S NAUTIYAL
CELL : 9820313278
 |
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.
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