Request a quote
(281) 441-4088

LATEST News

A Brief History of Carbon Steel – Part 2
For more info on this topic, check out last month’s post A Brief History of Carbon Steel – Part 1Carbon steel wasn’t always the reliable metal that we use for our blind flanges and forged steel rings that we use…



What Are the Components of a Wellhead and What Do They Do? – Part 1
FCI is one of the top wellhead component suppliers in the country, but what are the components of a wellhead and what do they do? This series of blog posts will explain these components and how they work within the…



A Brief History of Carbon Steel – Part 1
Carbon steel first appeared around the year 500 AD in Damascus steel swords as well as Japanese swords. They were prized for their sharp edges and sturdiness compared to other weapons of the era. The composition of these swords was…



Long Weld Neck Flanges – What are They Used for?
Where “standard” weld neck flanges are used extensively for pipes, long weld neck flanges (often abbreviated to LWN) are used in high pressure and high (or fluctuating) temperature situations primarily in the oil and gas industry. The long neck guides…



What is the Difference between ANSI and ASME Flanges?
The short answer is not a lot. ANSI is an abbreviation for the American National Standards Institute, a non-profit organization composed of members from a wide cross-section of individuals associated with them in academia, government agencies, businesses and organizations that…



Bolt and Nut Dimensions

Stud
Bolt
Size

Thread Dimensions

Nut Dimensions

Threads
Per Inch

Root
Area

Across
Flats

Across
Corners

Nom.
Thick.

1/2

13

0.126

0.875

0.969

0.484

5/8

11

0.202

1.063

1.175

0.609

3/4

10

0.302

1.250

1.383

0.734

7/8

9

0.419

1.438

1.589

0.859

1

8

0.551

1.625

1.796

0.984

1 1/8

8

0.728

1.813

2.002

1.109

1 1/4

8

0.929

2.000

2.209

1.219

1 3/8

8

1.155

2.188

2.416

1.344

1 1/2

8

1.405

2.375

2.622

1.469

1 5/8

8

1.680

2.563

2.828

1.594

1 3/4

8

1.980

2.750

3.035

1.719

1 7/8

8

2.300

2.938

3.242

1.844

2

8

2.650

3.125

3.449

1.969

2 1/4

8

3.420

3.500

3.862

2.203

2 1/2

8

4.290

3.875

4.275

2.453

2 3/4

8

5.260

4.250

4.688

2.703

3

8

6.320

4.625

5.102

2.953

3 1/4

8

7.490

5.000

5.515

3.188

3 1/2

8

8.750

5.375

5.928

3.438

3 3/4

8

10.110

5.750

6.341

3.688

4

8

11.570

6.125

6.755

3.938

Calculation of "Nut Stop Diameter"
Nut Stop Diameter = Bolt Circle Diameter - Nut Dimension Across Flats
Example:
Determine nut stop diameter of a 16" - 300# RF Equal Barrel 'E' connection

DESIGN DATA
Bolt Circle Diameter = 22.50 inches (ref. 16" - 300# RF flange bolt circle)
Stud Bolt Size = 1.25 inches (ref. 16" - 300# RF flange)
Nut Dimension Across Flats = 2.00 inches (ref. above chart for nut dimension relating to stud bolt size)

Nut Stop Diameter = Bolt Circle Diameter - Nut Dimension Across Flats
Nut Stop Diameter = 22.50 - 2.00 = 20.50 in.

NOTE:
Technical data contained in this section governed by ASME or other Codes/Specifications are subject to change and are therefore provided for information purposes only and are not to be used for design purposes. Refer to latest edition of applicable Code/Specification and addendums thereto for required design data.