8620 SNCM220 1.6523 20NiCrMo2-2 Cold Rollled Seamless Steel Tube
8620 SNCM220 1.6523 20NiCrMo2-2 Cold Rollled Seamless Steel Tube

Item specifics

Outer diameter
83-254 mm
Wall thickness
7 to 60 mm
length
12 meters
Cold drawn tolerance for OD and ID
within ±0.2mm
Cold rolled tolerance for OD and ID
within ±0.1mm

Review

Description

Application

AISI 8620 Steel is a low alloy nickel, chromium, molybdenum case hardening steel, generally supplied in the as rolled condition with a maximum hardness HB 255max. SAE steel 8620 offers high external strength and good internal strength, making it highly wear resistant. AISI 8620 steel has a higher core strength than grades 8615 and 8617.
Annealing
AISI 8620 steel may be given a full anneal by heat to 820℃ – 850℃, and hold until temperature is uniform throughout the section and cool in furnace or air cooled.
Standard

Specifications

Dimensions:Outer diameter: 83-254 mm, Wall thickness: 7 to 60 mm, length: not more than 12 meters.

Tolerance for OD and ID:
Cold drawn: within ±0.2mm
Cold rolled: within ±0.1mm

Tolerance for Wall Thickness:
Hot rolled: within +/-5%,
Cold drawn: within 0.6mm

Process:Hot Rolled, Cold Drawn, Precision Rolled
 
Delivery Condition:Hot rolled, Cold drawn, Annealed, Normalized, Quenched and tempered.

Surface Condition:Black surface, Rough turned, Peeled.

Chemical requirements: 

Grade

C

Mn

Pmax.

Smax.

Si

Cr

Mo

Ni

8620

0.18-0.23

0.70-0.90

0.04

0.04

0.15-0.35

0.40-0.70

0.40-0.60

0.15-0.25

Mechanical Properties
PropertiesMetricImperial
Tensile strength530 MPa76900 psi
Yield strength385 MPa55800 psi
Elastic modulus190-210 GPa27557-30458 ksi
Bulk modulus (typical for steel)140 GPa20300 ksi
Shear modulus (typical for steel)80 GPa11600 ksi
Poisson’s ratio0.27-0.300.27-0.30
Izod Impact115 J84.8 ft.lb
Hardness, Brinell149149
Hardness, Knoop (converted from Brinell hardness)169169
Hardness, Rockwell B (converted from Brinell hardness)8080
Hardness, Vickers (converted from Brinell hardness)155155
Machinability (hot rolled and cold drawn, based on 100 machinability for AISI 1212 steel)6565
AISI 8620 Steel Grade Heat Treatment
Tempering
Tempering of heat treated and water quenched parts of 8620 steels (not carburized) is done at 400 F to 1300 F to improve case toughness with minimal effect on its hardness. This will also reduce the possibility of grinding cracks.

Hardening
The AISI steel 8620 will be austenitized at around 840°C – 870°C, and oil or water quenched depending upon section size and intricacy. Cool in Air or Oil required.

Normalizing
1675ºF (910ºC) and air cool. This is another method of improving machinability in 8620 material; normalizing might also be used prior to case hardening.


This alloy is used in the oil and gas industry as forged down-hole drilling tools such as drill collars. Other applications are forged gears, shafts for hydraulic presses, rolls for paper mills, pump shafts and tool holders
8620 steel