Heat Treating

AMERICAN CENTRIFUGAL's complete heat treating facilities include equipment for precise electronic control of all operations. Vertical furnaces and quench tanks are adjacent for rapid transfer of tubing from furnace to quench.

Full length tubes are suspended vertically. Both water and oil quench facilities are available.

AMC Temperature Range -- 900° to 2150°F

Number	Type	Capacity
2	Vertical Pit Type Furnaces	84" Diameter by 24' deep.
2	Vertical Pit Type Furnaces	106" Diameter by 25' deep.
1	Vertical Water Quench Tank	69" Diameter by 20' deep
1	Vertical Oil Quench Tank	84" Diameter by 22' deep.
1	Car Type Furnace	180" wide, 264" high, 35' long.
4	Car Type Furnaces	60" wide, 54" high, 12' long.
3	Car Type Furnaces	17' wide, 22' high, 35' long.

AMC Temper Furnace, ± 10° F

Number Type Capacity

1 Twin Hearth Box Furnace 12'-6" wide, 6'-5" high, 24'-10" long

Toughness Enhancement

CHARPY V--NOTCH IMPACT ENERGY VALUES AT 70 DEGREES F
ASTM A27 GRADE N-1 CENTRIFUGAL CASTINGS
AS CAST AND HEAT-TREATED (N&T AT 1150 degrees)

Toughness enhanced by heat treatment is demonstrated by test results reported in this figure. Heat treatment increased the impact energy values up to nine fold.

Dimensional Stability

In recent years, applications for tubular steel products have become more sophisticated and consequently, require a greater degree of dimensional stability. AMERICAN CENTRIFUGAL made an investigation of the comparison of relative dimensional stability between a representative hot roll seamless steel tube (HRSST) and a centrifugally cast steel tube (AMERICAN). Comparisons of changes of measured circumferential strain are shown in the figure, below.

CHANGE OF CIRCUMFERENTIAL STRAIN
AS WALL THICKNESS IS REDUCED

Relationship of the change of circumferential strains as the wall thicknesses were reduced by machining material from the outside. Gauges were mounted on the inside surface, on a circumferential plane, 90° apart. Note: strains are not cumulative.