welding brazing pipe tube

8/3/2019 Welding Brazing Pipe Tube

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from wikipedia :

Brazing is a metal-joining process whereby a filler metal is heated above and

distributed between two or more close-fitting parts by capillary action. The filler

metal is brought slightly above its melting (liquidus) temperature while protected by

a suitable atmosphere, usually a flux. It then flows over the base metal (known as

wetting) and is then cooled to join the workpieces together.[1] It is similar to

soldering, except the temperatures used to melt the filler metal are above 450 C

(842 F).

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Welding is a fabrication or sculptural process that joins materials, usually metals or

thermoplastics, by causing coalescence. This is often done by melting theworkpieces and adding a filler material to form a pool of molten material (the weld

pool) that cools to become a strong joint, with pressure sometimes used in

conjunction with heat, or by itself, to produce the weld.

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This is in contrast with soldering and brazing, which involve melting a lower-

melting-point material between the workpieces to form a bond between them,

without melting the workpieces.

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in brief

WELDING you melt the workpieces as well as the filler material causing

coalescence (coalescence - the union of diverse things into one body or form) so

the seperate pieces become one piece

BRAZING you join the work without melting the workpieces but using a melted filler

to join them

here the pieces to be joined are still seperate but the gap between them is filled

with the solidified weld pool

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re: pipe and tube (also from wikipedia)


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A pipe is a tubular section or hollow cylinder, usually but not necessarily of circular

cross-section, used mainly to convey substances which can flow liquids and

gases (fluids), slurries, powders, masses of small solids. It can also be used for

structural applications; hollow pipe is far stiffer per unit weight than solid members.

In common usage the words pipe and tube are usually interchangeable |

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but in industry and engineering, the terms are uniquely defined. Depending on the

applicable standard to which it is manufactured, pipe is generally specified by a

nominal diameter with a constant outside diameter (OD) and a schedule that

defines the thickness.

Tube is most often specified by the OD and wall thickness, but may be specified by

any two of OD, inside diameter (ID), and wall thickness.

Pipe is generally manufactured to one of several international and national

industrial standards.[1]

While similar standards exist for specific industry application tubing, tube is often

made to custom sizes and a broader range of diameters and tolerances. Many

industrial and government standards exist for the production of pipe and tubing.

The term "tube" is also commonly applied to non-cylindrical sections, i.e., square or

rectangular tubing. In general, "pipe" is the more common term in most of the

world, whereas "tube" is more widely used in the United States.

Both "pipe" and "tube" imply a level of rigidity and permanence, whereas a hose (or

hosepipe) is usually portable and flexible. Pipe assemblies are almost always

constructed with the use of fittings such as elbows, tees, and so on, while tube may

be formed or bent into custom configurations. For materials that are inflexible,

cannot be formed or where construction is governed by codes or standards, tube

assemblies are also constructed with the use of tube fittings.

soooo... PIPE is cylindrical but not always round in cross section ,

usually categorized by the outside diameter and a schedule that defines the

thickness(whatever that means)and

is made to recognized standards as a rule.


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pipes are almost always constructed using fittings to go round corners etc

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TUBE can be cylindrical but can also be a non cylindrical section(i.e. square or

rectangular cross section)

is usually categorised by any two of the following

outside diameter......inside diameter.....wall thickness

is often made to customized sizes and covers a broader range of applications and

tolerances than a pipe.

Tubes can be formed and bent into shape for specific applications or where this is

not possible because of the nature of the materials used, or to comply with

government or industry standards, tube fittings can be used.

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the difference between welding and brazing

in welding the two pieces melt themselves together using a weld pool of a different

material which makes a mixture of all three things so they actually combine to join

them together

Brazing the two pieces are joined by a melt of another metal but they do not melt

and mix together so it is actually still 3 separate components more like gluing them

together with molten metal

the difference between pipes and tubes

pipes are always cylindrical ie rounded but not always circular in cross section

tubes are not always cylindrical

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pipes are limited in the range of sizes and tolerances,pipes are generally only

available in certain recognized sizes


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tubes are more versatile and available in custom sizes for specific uses

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pipes are almost always joined using additional pieces to change direction

tubes are often bent to go round corners etc

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it is harder to explain the difference between tube and pipe

as the difference is less clear

welding brazing pipe tube

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