brazing vs. silver solder

Rod Bixler

We where wondering what pressures a brazed joint can hold compared to a silver soldered one????

Glen Aspen_2

It Depends -

but are you asking the difference between soft solder and silver solder? Silver solder or brazing is often considered the same - and then lastly - which materials are you joining? For copper to copper; it depends on operating pressure, working temperature and size of pipe.

Rod Bixler

rbix@cvn.net

brazing is done at a much higher temperature than silver soldering. So much so that you need to use nitrogen flowing through the tubing to prevent oxidation or flaking inside the tubing. We where talking about joining copper refrigerant lines and the pressures that the two different joints could with stand.

Glen Aspen_2

According to one resource

Brazing alloys above 1000 deg F:

to 1 inch - 350 deg @ 270 psi

to 2 inch - 350 deg @ 190 psi

to 4 ich - 350 deg @ 150 psi

(IPT Pipe Trades Manual)

The manual lists temp/pres charts to 12 inch copper tube.

Techman

pressure

Hi guy's,Here's my slang from neumerous sources.800* and lower is sometimes  called solder,soldering,soft solder,silver solder,Silver bearing soft solder,StayBrite,and" The one on the roll " and" Not the stick stuff"and I'm sure there are others.And for above 800* it's brazing,hard solder, silver braze and the stick stuff.The tensile strength of 15% silphos is 86,000psi and the tensile strength of Stay-Brite is 15,000psi.The tube burst strength  of the copper  and the fitting drops from 3,800psi down to 1,800 psi by brazing,not so for soldering.