What is the main disadvantage of a braze welded joints?
What is the main disadvantage of a braze welded joints?
One of the main disadvantages is the lack of joint strength as compared to a welded joint due to the softer filler metals used. The strength of the brazed joint is likely to be less than that of the base metal(s) but greater than the filler metal.
How do you inspect a brazed joint?
Braze joints are typically tested using a straight beam test that monitors the amplitude of the echo from the braze location at the inner surface of the outer metal part.
What is wetting in brazing?
The term “wetting” is commonly used to describe the flow of braze alloy or braze filler across a surface via capillary action; it is critical for a successful braze joint.
Is a brazed joint stronger than a soldered joint?
Brazing is much stronger than soldering, and unlike many other production processes, it is ideal for joining dissimilar materials. Brazing is a versatile joining method that produces a permanent, strong, leak-proof joint.
What are the precautions necessary in brazing?
Safety glasses, goggles, face shields, helmets, or other suitable eye protection having the proper lens shade for the work being done shall be worn during all welding, cutting, and brazing operations. Fire Watch personnel shall wear eye and face protection as appropriate.
Which brazing joint is strongest?
Both scarf and butt joints when properly made with silver brazing alloys are considerably stronger than the parent material. Unfortunately scarf joints are more difficult to hold in alignment than the square-butt or lap joints.
What causes porosity in brazing?
Voids or porosity – an incomplete flow of brazing filler metal which can decrease joint strength and allow leakage-often caused by improper cleaning, incorrect joint clearance, insufficient filler metal, entrapped gas or thermal expansion.
What is a peel test brazing?
The peel test is to check for voids in the brazed joint. In the case of pipe, the joint is always a lap joint that is in the shape of a socket fitting. The peel test is performed like it would be for any lap join, just cut the pipe into quadrants so you can work it easier.
What is the filler material for brazing?
A brazing filler begins with one of several common primary metals: silver, aluminum, gold, copper, cobalt or nickel. These primary metals are then mixed, or alloyed, with other metals to improve or tweak their properties.
Is brazing watertight?
Brazing offers many advantages over spot welding or soldering. For instance, a brazed joint is smooth and complete, creating an airtight and watertight bond for piping that can be easily plated so the seam disappears. It also conducts electricity like the base alloys.
What PPE is required for brazing?
All operators and attendants of resistance welding or resistance brazing equipment shall use transparent face shields or goggles, depending on the particular job, to protect their faces or eyes, as required.
What are 3 reasons why you should use flux when brazing?
Why Brazing Requires Flux If you don’t stop these oxides from forming, they’ll inhibit the brazing filler metal from wetting and bonding to the surfaces. A coating of flux on the joint area guards the surfaces from the air, preventing oxide formation.
What causes voids and porosity in brazing metal?
Voids or porosity – an incomplete flow of brazing filler metal which can decrease joint strength and allow leakage-often caused by improper cleaning, incorrect joint clearance, insufficient filler metal, entrapped gas or thermal expansion.
Why do I have voids in my braze joints?
Brazers commonly encounter voids in brazed joints and often wonder where they come from and how to avoid them in future brazements. Some common sources of voids in braze joints are: Base metal and brazing filler metal (BFM) constituents The first three items listed above can often result in gas bubbles being formed in brazed joints.
What are the common discontinuities of brazed joints?
Discontinuities Common discontinuities of brazed joints, identified through nondestructive examination, include: Voids or porosity – an incomplete flow of brazing filler metal which can decrease joint strength and allow leakage-often caused by improper cleaning, incorrect joint clearance, insufficient filler metal,…
Is there porosity in the braze fillet?
As you can see in the photograph, the brazed joint itself is fine, with no porosity or cracks, even those the top surface of the braze fillet appears to be a bit rough.