STS Industrial - Bolts & Screws

 

ASTM A193 GRADE B7 PTFE COATED STUD BOLTS

GOVERNING STANDARDS:
ASTM A193/A193M Standard specification for alloy-steel and stainless steel bolting for high temperature or high pressure service and other special purpose applications.
ASME B16.5 Covers recommended stud bolt quantity, diameter, and length for use in flanged pipe fittings.
ASME B1.1 Class 2A Specifies the thread form, series, class, allowance, tolerance, and desig nation for unified screw threads. UNC for 1″ diameter and smaller. UN8 (8 threads per inch) for 1-1/8″ diameter and larger.

 

APPLICATIONS:

Common / economical fully threaded stud bolt for use in high temperature and high pressure applications in refineries, chemical plants, pipelines, power plants, and other industries. FluroKote1® PTFE coating increases resistance to chemical and atmospheric corrosion and provides excellent lubricity.

COATING:

FluroKote1® fluoropolymer PTFE coating is formulated with superior characteristics for maximum fastener life. Technical components include a tensile strength of up to 4,000 psi and an operating pressure up to 100,000 psi. The absence of nut locking oxides enable easy and safe removal of nuts years after installation. FluroKote1® has extreme chemical resistance and is ideal for applications including insulating piping, boiler rooms, water filled piping, water lines and more.

Due to its unique benefits, FluoroKote#1® applications have been used for various types and grades of fasteners. The water works industry takes advantage of the superior corrosion resistance properties by coating T-head bolts for underground service. Stainless steel fasteners, used in many different industries, are coated for lubricity and anti-galling. The most widely used application is on B7 studs with 2H nuts. These fasteners are commonly used by turnaround groups, operations and maintenance departments, and contractors at many chemical plants, refineries, and offshore platforms.

ASTM A193 Grade B7 Stud Bolt Marking

Product to be marked with the manufacturer’s marking and grade marking on one end of each stud 3/8″ diameter and larger. Manufacturer’s marking may be placed on other end if insufficient space. 

 

MATERIAL PROPERTIES:
Chromium- Molybdenum Alloy Steel, AISI 4140, 4142, 4145, 4140H, 4142H or 4145H Quenched and Tempered

DIAMETER

PROOF LOAD

YIELD STRENGTH

TENSILE STRENGTH

CORE HARDNESS

up through 2-1/2″

105,000 psi 125,000 psi

C35 Max

2-5/8″ through 4″

95,000 psi 115,000 psi

C35 Max

>4” through 7”

75,000 psi 110,000 psi

C35 Max

Elongation 16% Minimum for diameters through 4”, 18% Minimum for diameters over 4” through 7”
Reduction of Area 50% Minimum (All Diameters)
Material strengths listed are minimum acceptable per governing standard. Core hardness based on Rockwell scale.

 

STUD REFERENCE CHART:

The chart below gives the recommended stud bolt diameter, length, and quantity for a given flange size.

FLANGE NOMINAL PIPE DIAMETER (in.)
RATING BOLTING 1/2 3/4 1 1-1/4 1-1/2 2 2-1/2 3 3-1/2 4
150# Number 4 4 4 4 4 4 4 4 8 8
Diameter 1/2 1/2 1/2 1/2 1/2 5/8 5/8 5/8 5/8 5/8
Stud Bolt Length 2-1/4 2-1/2 2-1/2 2-3/4 2-3/4 3-1/4 3-1/2 3-1/2 3-1/2 3-1/2
Mach Bolt Length 2 2 2-1/4 2-1/4 2-1/2 2-3/4 3 3 3 3
300# Number 4 4 4 4 4 8 8 8 8 8
Diameter  1/2  5/8  5/8  5/8  3/4  5/8  3/4  3/4  3/4  3/4
Stud Bolt Length 2-1/2 3 3 3-1/4 3-1/2 3-1/2 4 4-1/4 4-1/4 4-1/2
Mach Bolt Length 2-1/4 2-1/2 2-1/2 2-3/4 3 3 3-1/4 3-1/2 3-3/4 3-3/4
600# Number 4 4 4 4 4 8 8 8 8 8
Diameter  1/2  5/8  5/8  5/8  3/4  5/8  3/4  3/4  7/8  7/8
Stud Bolt Length 3 3-1/2 3-1/2 3-3/4 4-1/4 4-1/4 4-3/4 5 5-1/2 5-3/4
900# Number 4 4 4 4 4 8 8 8 8
Diameter  3/4  3/4  7/8  7/8 1  7/8 1 7/8 1-1/8
Stud Bolt Length 4-1/4 4-1/2 5 5 5-1/2 5-3/4 6-1/4 5-3/4 6-3/4
1500# Number 4 4 4 4 4 8 8 8 8
Diameter  3/4  3/4  7/8  7/8 1  7/8 1 1-1/8 1-1/4
Stud Bolt Length 4-1/4 4-1/2 5 5 5-1/2 5-3/4 6-1/4 7 7-3/4
2500# Number 4 4 4 4 4 8 8 8 8
Diameter  3/4  3/4  7/8 1 1-1/8 1 1-1/8 1-1/4 1-1/2
Stud Bolt Length 4-3/4 5 5-1/2 6 6-3/4 7 7-3/4 8-3/4 10
FLANGE NOMINAL PIPE DIAMETER (in.)
RATING BOLTING 5 6 8 10 12 14 16 18 20 24
150# Number 8 8 8 12 12 12 16 16 20 20
Diameter 3/4 3/4 3/4 7/8 7/8 1 1 1-1/8 1-1/8 1-1/4
Stud Bolt Length 3-3/4 4 4-1/4 4-1/2 4-3/4 5-1/4 5-1/4 5-3/4 6-1/4 6-3/4
Mach Bolt Length 3-1/4 3-1/4 3-1/2 4 4 4-1/2 4-1/2 5 5-1/2 6
300# Number 8 12 12 16 16 20 20 24 24 24
Diameter  3/4  3/4  7/8 1 1-1/8 1-1/8 1-1/4 1-1/4 1-1/4 1-1/2
Stud Bolt Length 4-3/4 4-3/4 5-1/2 6-1/4 6-3/4 7 7-1/2 7-3/4 8 9
Mach Bolt Length 4-1/4 4-1/4 4-3/4 5-1/2 5-3/4 6-1/4 6-1/2 6-3/4 7-1/4 8
600# Number 8 12 12 16 20 20 20 20 24 24
Diameter 1 1 1-1/8 1-1/4 1-1/4 1-3/8 1-1/2 1-5/8 1-5/8 1-7/8
Stud Bolt Length 6-1/2 6-3/4 7-1/2 8-1/2 8-3/4 9-1/4 10 10-3/4 11-1/4 13
900# Number 8 12 12 16 20 20 20 20 20 20
Diameter 1-1/4 1-1/8 1-3/8 1-3/8 1-3/8 1-1/2 1-5/8 1-7/8 2 2-1/2
Stud Bolt Length 7-1/2 7-1/2 8-3/4 9-1/4 10 10-3/4 11-1/4 12-3/4 13-3/4 17-1/4
1500# Number 8 12 12 12 16 16 16 16 16 16
Diameter 1-1/2 1-3/8 1-5/8 1-7/8 2 2-1/4 2-1/2 2-3/4 3 3-1/2
Stud Bolt Length 9-3/4 10-1/4 11-1/2 13-1/4 14-3/4 16 17-1/2 19-1/2 21-1/4 24-1/4
2500# Number 8 8 12 12 12
Diameter 1-3/4 2 2 2-1/2 2-3/4
Stud Bolt Length 11-3/4 13-1/2 15 19-1/4 21-1/4

All dimensions in inches unless otherwise noted.

Sources: ASTM Standards for Mechanical Fasteners and Related Processes 2nd Edition, Inch Fastener Standards 8th Edition

Note: All material included on this page is informational only, and should not be used as one’s sole source for design purposes. STS Industrial, Inc. and its affiliates do not guarantee the accuracy of the information on this site, and retain no liability for the use or misuse of the information contained on this site.