AISI 4140 / ASTM A193 Grade B7 Cold Drawn QT Plain Steel Round Bars
ASTM A193 Grade B7 Chromium Molybendum steel, normally AISI 4140, heat treated to 28-32Rockwell Hardness, 125,000 PSI tensile strength, 105, 000 PSI yield. It will hold it's strength to 1000 degrees F.
ASTM A193 Grade B7 Threaded Rod is a kind of high strength and heat resistant threaded rod manufactured from 4140/4142 quenched and tempered alloy steel for high temperature or high pressure service, used by the plumbing and contracting trade in maintenance departments to secure pressure tanks, valves, and flanges.
1.A193 B7 round bar Chemical composition: (raw material aisi 4140 )
| Grade |
C |
Si |
Mn |
P |
S |
Cr |
Mo |
| SAE 4140 |
0.37-0.49 |
0.15-0.35 |
0.65-1.1 |
Max0.035 |
Max0.04 |
0.75-1.20 |
0.15-0.25 |
2.A193 B7 Round Bar Properties:
| Tensile Strength |
Yield Strength |
Elongation |
Reduction Area |
Hardness |
| Mpa |
MpA |
% |
% |
HRC |
| min860 |
min720 |
min12 |
min50 |
max35 |
3.Sizes of A193 B7 QT steel bars we can supply :
Hot rolled steel round bar :M12-M310
Hot Rolled & QT (Quenched and tempered): M12-M120
Cold Drawn&QT (Quenched and tempered):M6-M120
Peeled+QT(Quenched and tempered):M20-M120
4.A193 B7 QT bars packing : surface oiled+ Woven cloth
5.Straightness of QT bars: Max 1mm/m (important )
6.Payment terms: T/T or L/ C
(1)30% paid by T/T and rest 70% by T/T upon the copy of B/B.
(2)100% irrevocable L/C at sight
7.Delivery time:within 7 days after your deposit or L/C.
8.Mark: including steel material, heat No., pieces, weight, date and so on.
9.Quality control
1.Process for Steel round bar
Blast Furnance→ Molten Iron Pretreatment→Converter→LF→VD/RH→ContinuousCasting→Hot Rolling(KOCKS)→ Heat Treatment→ UT Inspection→Finish Product
EAF→LF→VD/RH→ Continuous Casting→Hot Rolling(KOCKS)→ Heat Treatment→ UT Inspection→ Finish Product
2.Grain Sizes:5-8
3.Surface condition: The surface of the bar shall be free cracks, scar and wrinkles at affect the use of the billets.
4.The mill test certificate shall show the chemical composition, and it is guaranteed that the chemical composition shall be within the limit stipulated in the contract
Audited Supplier 
){kind=link}