AISI 4330V Material Bar, Hollow Bar Forging for High Strength
Modified 4330V bar or hollow bar for high strength components
possesses good fracture toughness. This material is generally not
suitable for sour service. Products containing load bearing parts
manufactured to this specification should be not used in installed
sour service applications.
Melt Practice and Condition
The steel shall be electric furnace melted and refined using
practices capable of producing fine grained materials free from
The materials shall be supplied in the quenched and tempered
condition and shall be free from excessive banding. The minimum
reduction ratio during forging shall be 4:1 except where solid bar
is supplied greater than 240mm (9.5’’) diameter, in which case the
minimum forging ratio shall be 2.5. The minimum tempering
temperature shall be 580°C(1076°F).
The chemical composition shall be determined in accordance with
ASTM A751 and shall meet the requirements in weight percent for the
specific grade as listed in the table below.
The surface hardness shall be as listed below as measured by ASTM
E18 or E10. The mechanical properties shall be referenced from the
relevant Engineering drawing determined at the approximate
mid-radial location in accordance with ASTM A370 and shall be
within the following ranges.
|Minimum yield as referenced from the Engineering Drawing 0.2% Proof
Stress ksi ||Mid Radial Mechanical Properties|| |
|0.2% Proof Stress,|
|Reduction of Area, %||Hardness,|
|140||Min.||140 (966)||165 (1172)||15||45||36 (336)|
|Max.||-||190 (1310)||-||-||42 (390)|
|130||Min.||130 (897)||160 (1103)||15||45||34 (321)|
|Max.||-||180 (1241)||-||-||40 (375)|
|120||Min.||120 (828)||150 (1034)||15||45||32 (302)|
|Max.||-||170 (1172)||-||-||38 (352)|
|110||Min.||110 (759)||140 (966)||15||45||30 (285)|
|Max.||-||160 (1103)||-||-||36 (331)|
The heat identification and heat treatment lot traceability shall
be maintained through all stages of processing.
Surface shall be free from cracks, laps, seams and other surface
Material certification shall be prepared for each heat and heat
treat lot of material. Material certification shall be provided in
accordance with BS EN 10204 Type 3.1. As a minimum, the
certification shall contain the following: statement of compliance
with this specification, chemical analysis results, mechanical test
results, heat/heat treat batch identification and purchase order.