ASTM A193 is the standard specification for alloy-steel and stainless steel bolts used in high-temperature or high-pressure environments or other special-purpose applications.
ASTM A194 is the standard specification for carbon and alloy steel nuts for bolts used in equivalent high-pressure or high-temperature environments.
ASTM A193 and A194 bolts and nuts from Glaser and Associates are available in a range of grades, including B7, B16 B8 and B8M to meet different design,
service conditions, mechanical properties, and high temperature requirements. ASTM A194 also covers the American Association State Highway and
Transportation Officials Standard AASHTO M-292.
These bolts and nuts are designed, manufactured and tested to comply with the standards set by ASTM A193 and A194 for chemical composition,
tensile and hardness properties and high temperature characteristics.
Grades
|
Grade
|
Material
|
|
B7
|
Alloy steel, AISI 4140/4142 quenched and tempered
|
|
B16
|
Alloy steel, Chromium-molybdenum-vanadium heat treated
|
|
B8
|
Class 1 Stainless steel, AISI 304, carbide solution treated
|
|
B8M
|
Class 1 Stainless steel, AISI 316, carbide solution treated
|
|
B8
|
Class 2 Stainless steel, AISI 304, carbide solution treated, strain hardened
|
|
B8M
|
Class 2 Stainless steel, AISI 316, carbide solution treated, strain hardened
|
B7, B8 and B8M are the most commonly used grades. The properties tables below provide more information on the differences between the grades.
Applications
The high-temperature, high-pressure performance of these bolts and nuts make them suitable for applications in process industries,
such as petroleum and chemicals where they are widely used in pressure vessels, valves, flanges, and fittings.
Properties
|
Grade
|
Size
|
Tensile ksi, min
|
Yield, ksi, min
|
Elong, %, min
|
RA % min
|
|
B7
|
Up to 2-1/2
|
125
|
105
|
16
|
50
|
|
2-5/8 - 4
|
115
|
95
|
16
|
50
|
|
4-1/8 - 7
|
100
|
75
|
18
|
50
|
|
|
Up to 2-1/2
|
125
|
105
|
18
|
50
|
|
B16
|
2-5/8 - 4
|
110
|
95
|
17
|
45
|
|
|
4-1/8 - 7
|
100
|
85
|
16
|
45
|
|
B8 Class 1
|
All
|
75
|
30
|
30
|
50
|
|
B8M Class 1
|
All
|
75
|
30
|
30
|
50
|
|
B8 Class 2
|
Up to 3/4
|
125
|
100
|
12
|
35
|
|
7/8 - 1
|
115
|
80
|
15
|
35
|
|
1-1/8 - 1-1/4
|
105
|
65
|
20
|
35
|
|
1-3/8 - 1-1/2
|
100
|
50
|
28
|
45
|
|
B8M Class 2
|
Up to 3/4
|
110
|
95
|
15
|
45
|
|
7/8 - 1
|
100
|
80
|
20
|
45
|
|
1-1/8 - 1-1/4
|
95
|
65
|
25
|
45
|
|
1-3/8 - 1-1/2
|
90
|
50
|
30
|
45
|
|
Element
|
B7
|
B8
|
B8M
|
|
Carbon
|
0.37 - 0.49%
|
0.08% max
|
0.08% max
|
|
Manganese
|
0.65 - 1.10%
|
2.00% max
|
2.00% max
|
|
Phosphorus, max
|
0.035%
|
0.045%
|
0.045%
|
|
Sulfur, max
|
0.040%
|
0.030%
|
0.030%
|
|
Silicon
|
0.15 - 0.35%
|
1.00% max
|
1.00% max
|
|
Chromium
|
0.75 - 1.20%
|
18.0 - 20.0%
|
16.0 - 18.0%
|
|
Nickel
|
8.0 - 11.0%
|
10.0 - 14.0%
|
|
Molybdenum
|
0.15 - 0.25%
|
2.00 - 3.00%
|
