ASTM A193 B8MA Stud Bolt with A194 8MA Hex nuts

Professional manufacturer of ASTM A193 B8MA Stud Bolt with A194 8MA Hex nuts in China

What is the ASTM A193 Grade B8MA?

Grade B8MA ,the same as Grade B8M Made from AISI 316 austenitic stainless steel used throughout the Oil and Gas industry for general connections including valves, flanges, and fittingstainless steel.

B8MA,B refers to Bolt material,8 refers to 8% nickel ,M means molybdenum (Mo)added. A,refers to  Annealed heat tre

Annealed Condition (Class A):

The annealing process enhances ductility and toughness, making the material suitable for critical applications.

ASTM A193 B8MA Stud Bolt Chemical composition

Chemical Requirement
AISI  316
Grade

C

Mn

P

S

Si

Mo

Ni

Cr

B8M,
B8MA
B8M2

Max

Max

Max

Max

Max

0.08

2.00

0.045

0.030

1.00

2.00-3.00

10.00-14.00

16.00-18.00

ASTM A193 B8MA Stud Bolt Mechanical properties
Grade

Diameter

Tensile Strength kpsi (Mpa)

Yield Strength 0.2% Offset
kpsi (Mpa)

Elongation %

Hardness
MAX

min

min

min

HBS

HRC

B8M2
A4-80

<’2
‘2–2-1/2’
2-1/2–3’

95
90
80

75
65
55

40
40
60

–

35
35
35

B8M

–

75

30

50

223

B96

B8MA

–

75

30

50

192

B90

ASTM A193 B8MA Stud Bolt Specifications

Parameter Details
Material Grade ASTM A193 B8MA (316 SS, Annealed )
Thread Type UNC (coarse) or Metric Thread
Size Range 1/4″ to 4″ (M6 to M100 metric)
Length Range Standard and custom lengths
Finish Plain (uncoated) or PTFE Coated
Nuts Heavy hex nuts per ASTM A194 Gr. 8MA

Applications of ASTM A193 B8MA Stud Bolt

  1. Chemical Processing Plants:
  2. Marine and Offshore:
  3. Industrial Piping Systems:
  4. Power Generation:

Difference between ASTM A193 B8MA and ASTM A193 B8M Stud Bolt

Both ASTM A193 B8MA and ASTM A193 B8M stud bolts are made from AISI 316 stainless steel, but they are different in mechanical properties, heat treatment, and intended applications.

Material Condition

  • ASTM A193 B8MA:
    • The material is in the annealed condition (Class A).
    • The annealing process increases ductility and toughness, making it suitable for applications requiring flexibility and resistance to cracking.
  • ASTM A193 B8M:
    • Standard material with no specific designation for annealing.
    • Typically strain-hardened (cold worked) to enhance strength

The ASTM A193 B8MA stud bolt is a high-performance stainless steel fastener made from AISI 316 stainless steel in the annealed condition.