Intro 22
B
RASS
F
ITTINGS
CA360 Barstock Brass
ASTM B16 - 92
CA377 Forged Brass
ASTM B 124,283
Extruded Barstock Fittings
Hexagon, round and shaped bars are extruded in the
configuration required, drawn to size, cut to length and
straightened. First a solid round billet (8 to 12 inches in
diameter) is heated to the pliable state and forced by pressure
of approximately 80,000 pounds per square inch through a
die. The resulting continuous length of bar is cooled and then
drawn through dies to the desired external size. ( The drawing
process also controls the temper). After straightening, the bar
is ready for machining.
The process produces a dense, nonporous material somewhat
stronger in the longitudinal direction due to an orientated flow
of the grain.
Forged Fittings
Material for forging is extruded in round bars, cut to length
and straightened. (At this point in the process, forging rod
differs from round extruded machinable bars only in temper
and chemical properties). After straightening, the bars are cut
again into slugs (short lengths), reheated to the pliable state
and pressed under a pressure of approximately 25,000 pounds
per square inch between upper and lower die cavities. After
cooling, the flash is trimmed away and the forging blank is
ready for machining.
This process of forming under extreme pressure produces a
uniformly dense material of exceptional strength. Because
grain flow follows the contour, the fitting has high impact
strength and is resistant to mechanical shock and vibration.
Why Brass Fittings?
Brass fittings are popular because they are strong and
durable and hence widely used in industrial and residential
applications. The use of brass to make various fittings
provides a distinct look because of its yellow color. The
advantages of brass for fittings include its good corrosive
resistance, and also its plating, joining, polishing and finishing
characteristics. Brass as a material is easily machined and
hence can be given any shapes of the various types of fittings
available.
Features of Brass Fittings:
Brass fittings have certain unique features which make them
highly demanded. Some of these properties are as follows:
•
Brass fittings are characterized by good strength.
•
These fittings have excellent high temperature ductility.
•
They have reasonable cold ductility.
•
Fittings made of brass have good conductivity.
•
They are excellent in corrosion resistance.
•
Brass fittings have good bearing properties.
•
They have low magnetic permeability.
MATERIAL COMPOSITION
Elements
Nominal
Min
Max
Copper
61.5
60
63
Lead
3.1
2.5
3.7
Iron
.35
Other
.50
Zinc
35.4
Balance
Elements
Nominal
Min
Max
Copper
59.5
58
61
Lead
2
1.5
2.5
Iron
.30
Zinc
38
Balance
Material used for Brass Fittings
Straight bodies:
Barstock CA 360 or CA 345
Shape bodies:
Extruded barstock CA 360 or
Forged CA 377
Nuts:
Barstock CA 360 or
Forged CA 377