Filler metal selection for tube to tube sheet welding

[kissjxp]

I need your advice on the filler metal selection for tube to tube sheet welding (GTAW Process):

Tubesheet: SB171-46400 (Naval Brass, 60Cu-40Zn)
Tube-1: SB111-44300 (Admiralty Brass, 70Cu-30Zn)
Tube-2: SB111-71500 (70Cu-30Ni)

(1): what filler metal should be used for SB111-44300 to SB171-46400 welding?
(2): what filler metal should be used for SB111-71500 to SB171-46400 welding?

Is AWS A5.7 ERCuNi suitable for both item 1 and 2 above?

Thanks.

 

[metengr]

kissjxp;
No for both. The filler metal for joining brass to brass can be either ERCuSn-A or ERCuSi, and for Cu-Ni to brass, ERCuNi.

 

[strider6]

I'l use a filler metal with the composition of Cu/Ni 70/30

Joining Copper-Nickel Alloys

http://www.copper.org/applications/cuni/txt_joining_CN_alloys.html#dissimilar

http://www.copper.org/Applications/cuni/txt_properties.html#WeldingAndFabrication

copper nickel fabrication

http://www.stainless-steel-world.net/pdf/12014.pdf

http://www.twi.co.uk/content/jk23.html

S


Corrosion Prevention & Corrosion Control

 

[EdStainless]

Is this an attempt to repair an existing unit that has bad joints? If so then getting it clean enough could be a problem.
It is rare to see seal welds in Brass and CuNi units.

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Plymouth Tube

 

[kissjxp]

Thanks: METENGR, STRIDE6, and EdStainless

EdStainless:

If seal welds brass and CuNi can not be obtained, How to make the tube to tubesheet joint, Heavy expansion?