440C bearing steel round bar

PRODUCT NAME :bearing steel round bar ( forged ,rolled )
STANDARD:
GB/T18254-2002 ISO683-17
GRADE COMPARISION:

ULTRASONIC STANDARD:
GB/T6402-2008 / SEP921-84. ASTM A388
CHEMICAL COMPOSITION:

MANUFACTURING TECHNIQUE:
EFA+LF+VD(ESR)+ hot forged (hot rolled )
HEAT TREATMENT SPECIFICATION AND MECHANICAL PROPERTIES:

Annealing :800~920℃ cooling , quenching :1000~1050℃ oil cooling , tempering :200~ 300℃ air cooling.

Metallographic structure: martensite .

Annealed hardness ≤255HB; after Q&T≥55HRC

DELIVERY CONDITION :ANNEALED
SURFACE : BLACK / GRINDING / PEELING
DIMENSION : mm
Forged round bar :dia 80-450mm
Rolled round bar :dia 16-250mm
Coild rod : dia 5.5-20mm
Wire : dia 0.2-13mm
Rolled flat bar :thickness 5-90× width 44-300mm
Forged flat bar:thickness 120-800×width 120-800
length : forged bar free length 4-5.8M,rolled bar 5.8M. for customers special requirment, the bar length can do 20 meters long.
Tolerance on diameter of forged bar : black surface -0/+5mm, peeled surface -0/+3mm.
REMARK:
Above listed parameters and sepcification only for reference . Specific parameters according to standard. Requirments beyond standard will be negotiate by both sides .
Delivery state:normalized ,annealed, spheroidal annealed, quenched & tempered ,bright bar, cold-drawn, etc. Should be indicated in contract .
Listed specifications are only typical grades; products of required specifications can be developed/produced per international, Chinese or industry standards, or based
on agreements with customers.

Packing :
Forged bar , rolled bar and coil packing in loose . Rolled wire packing in plastic woven cloth or wooden case.
APPLIED RANGE:

Bearing steel is the general term for alloy steel used in the manufacture of bearing races and moving parts of all types of roller bearings. High carbon and chromium bearing steel is widely applied in the manufacture of pin rollers and sleeves on driving shaft used in auto components, construction machinery, combustion engines, electric locomotive, machine tools, tractors, steel rolling equipment, and drilling and exploration equipment for mining industry. Carburized bearing steel is mainly used in railway locomotives and wind turbines. The high-grade bearing steel products developed with proprietary technology have been highly appraised by six leading bearing manufacturers in the world.