0.25 Inch To 4 Inch B8M ASTM A193 Grade B7 Threaded Rod

Place of Origin CHINA
Brand Name QBH
Certification ISO9001
Model Number A193-B7
Minimum Order Quantity 900kg
Price 1200USD-2000USD/TON
Packaging Details 900KG/PALLET
Delivery Time 30days
Payment Terms L/C, T/T,OA
Supply Ability 600TON/MONTH
Product Details
Material Carbon Steel Size 1/4"-4"
Surface Treatment Plain,Zinc,Black,H.D.G Grade B7
Sample Free Sample Packaging 25kg Carton+900kg/Pallet
High Light

4 inch A193 Grade B7 Threaded Rod

,

A193 Grade B7 Threaded Rod

,

A193 304 Stainless Steel Threaded Rod

Leave a Message
Product Description

0.25 Inch To 4 Inch B8M ASTM A193 Grade B7 Threaded Rod

Originally approved in 1936, this specification is heavily utilized in petroleum and chemical construction applications. The ASTM standard covers alloy steel and stainless steel bolting materials for high temperature or high pressure service. This specification includes fasteners intended for use in pressure vessels, valves, flanges, and fittings. Although, this material is often available in national coarse (UNC) thread pitches, if being used in traditional applications, threads are specified 8 threads per inch (tpi) for diameters above one inch.

Below is a basic summary of a few of the common grades. ASTM A193 covers a number of other standard specifications not covered in this description including B5, B6, and B16.

0.25 Inch To 4 Inch B8M ASTM  A193 Grade B7 Threaded Rod 0

 

ASTM A193 Grade B7 Specification

ASTM A193 Grade B7 specification covers requirements for high tensile alloy steel bolting material for use in high temperature or high-pressure service and other special purpose applications. It is a standard specification defining typical chemical composition, mechanical properties, hardness requirement, preferential heat treatment, product marking, certification and other requirements, suitable for bolting used in pressure vessel service, valves, flanges and fittings. ASTM A193 defines both SI (Metric) and inch-pound units.

Grade B7 is a heat-treated chromium-molybdenum low-alloy steel with minimum tensile strength requirement of 125 ksi (860 Mpa), yield 105 ksi (720 Mpa), and maximum hardness of 35HRC. Boltport uses Alloy Steel AISI 4140 bar stock or forging stock to produce B7 headed and non-headed bolts. A193 Grade B7 is the most commonly used Bolt specification coupled with A194 Grade 2H Nuts for Bolting Carbon Steel pipeline. A193 B7 bolting is available in metric sizes from M6 to M180 and imperial sizes from 1/4 to 7 inches, in diameter.

Find information on ASTM A193 Grade B7 chemical composition, mechanical properties such as tensile strength; yield strength, hardness, marking requirements and reference product standards.

 

0.25 Inch To 4 Inch B8M ASTM  A193 Grade B7 Threaded Rod 1

 

ASTM A193 Grade B7 Chemical Composition

Elements Range Product Variation, Over or Under B
Carbon 0.37-0.49 % D 0.02 %
Manganese, max 0.65-1.10 % 0.04 %
Phosphorus, max 0.035 % 0.005 % over
Sulfur, max 0.040 % 0.005 % over
Silicon 0.15 - 0.35 % 0.02 %
Chromium 0.75-1.20 % 0.05 %
Molybdenum 0.15-0.25 % 0.02 %

B Product analysis - Individual determinations sometimes vary from the specified limits on ranges as shown in the tables. The several determinations of any individual element in a heat may not vary both above and below the specified range.

D For bar sizes over 31/2 in. [90 mm], inclusive, the carbon content may be 0.50 %, max. For the B7M grade, a minimum carbon content of 0.28 % is permitted, provided that the required tensile properties are met in the section sizes involved; the use of AISI 4130 or 4130H is allowed.

0.25 Inch To 4 Inch B8M ASTM  A193 Grade B7 Threaded Rod 2
 
 

Heat Treatment

B7 and B7M shall be heat treated by quenching in a liquid medium and tempering. For B7M fasteners, the final heat treatment, which may be the tempering operation if conducted at 1150 °F [620 °C] minimum, shall be done after all machining and forming operations, including thread rolling and any type of cutting. Surface preparation for hardness testing, nondestructive evaluation, or ultrasonic bolt tensioning is permitted.

Unless otherwise specified, material for Grade B7 may be heat-treated by the Furnace, the Induction or the Electrical Resistance method.

 

 

 

ASTM A193 Grade B7 Mechanical Properties - Metric Sizes

Diameter mm Min Tempering Temperature, °C Tensile Strength min, MPa Yield strength, min, 0.2% offset, MPa Elongation in 4D min, % Reduction of Area, min, % Hardness, max
M64 and Under 593 860 720 16 50 321 HBW or 35 HRC
over M64 to M100 593 795 655 16 50 321 HBW or 35 HRC
over M100 to M180 593 690 515 18 50 321 HBW or 35 HRC
 

ASTM A193 Grade B7 Mechanical Properties - Inch Sizes

Diameter Inch Min Tempering Temperature, °C Tensile Strength min, ksi Yield strength, min, 0.2% offset, ksi Elongation in 4D min, % Reduction of Area, min, % Hardness, max
2.5 and under 1100 125 105 16 50 321 HBW or 35 HRC
over 2.5 to 4 1100 115 95 16 50 321 HBW or 35 HRC
over 4 to 7 1100 100 75 18 50 321 HBW or 35 HRC
 

ASTM A193 Grade B7 Bolt Marking

QBH B7 "QBH" Manufacturer's Logo & "B7" Grade Marking
 

 

 

A193 Grades

B7 Alloy steel, AISI 4140/4142 quenched and tempered
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

A193 Mechanical Properties

Grade Size Tensile ksi, min Yield, ksi, min Elong, %, min RA % min HBW HRC
B7 Up to 2-1/2 125 105 16 50 321 max 35 max
2-5/8 - 4 115 95 16 50
4-1/8 - 7 100 75 18 50
B8 Class 1 All 75 30 30 50 223 max 35 max
B8M Class 1 All 75 30 30 50 223 max 96 max
B8 Class 2 Up to 3/4 125 100 12 35 321 max 35 max
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 45 321 max 35 max
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

A193 Chemical Properties

Element B7 (AISI 4140) B8 (AISI 304) B8M (AISI 316)
Carbon 0.38 - 0.48% 0.08% max 0.08% max
Manganese 0.75 - 1.00% 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 0.80 - 1.10% 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%

A193 Recommended Hardware

Bolt Grade Nuts Washers
B7 A194 Grade 2H F436
B8 Class 1 A194 Grade 8 SS304
B8M Class 1 A194 Grade 8M SS316
B8 Class 2 A194 Grade 8 SS304
B8M Class 2 A194 Grade 8M SS316