Full Thread Stud Bolt with Heavy Hex Nuts B8m for Flange Fastener

• Customization: Available
• Material: Stainless Steel
• Type: Round Head
• Model NO.: SBN-061
• Connection: Common Bolt
• Head Style: Round
• Standard: DIN, ANSI, GB, JIS, BSW, ASME, ISO, Hg
• Grade: 8.8
• Application: Machinery, Chemical Industry, Environmental, Building, B16.5 Flanges Connection
• Finish: PTFE Coating
• Surface Treatment: Plain
• Delivery: 2-4 Weeks
• Thread: Full Thread, Unc, Unf
• Length: According to Client's Requirement
• Size Range: M6-M100, 1/4"- 4"
• Transport Package: Plywood Cases/Wooden Boxes
• Specification: 1 5/8inch x 320mm
• Trademark: Qishine
• Origin: China
• HS Code: 7318159090
• Package Size: 35.00cm * 12.00cm * 12.00cm
• Package Gross Weight: 12.000kg

Product Description

Stud Bolt and Nuts

Flange connections are a widely used method for joining piping systems in industrial applications, requiring specialized fasteners capable of withstanding high loads, pressures, and maintaining leak-free seals. A prime example is the full thread stud bolt paired with heavy hex nuts, constructed from stainless steel grades ASTM A193 B8M and A194 8M.

Material Specifications

• ASTM A193 B8M: This specification covers high-performance bolting for high-temperature and high-pressure environments, with B8M being a corrosion-resistant grade. It is crafted from a high-strength austenitic stainless steel alloy containing molybdenum, which enhances resistance to pitting, crevice corrosion, and general corrosion in chloride-rich environments. This makes it ideal for chemical, petroleum, and marine industries.
• ASTM A194 8M: This specification governs nuts, with 8M referring to heavy hex nuts made from the same B8M stainless steel alloy as the stud bolts. Their heavy hex design provides a larger bearing surface, ensuring even load distribution and reducing the risk of dislodgement due to vibration or shock.

Advantages of Full Thread Stud Bolts

Unlike partially threaded bolts (which have a threaded portion and unthreaded shank), full thread stud bolts feature continuous threading from end to end. This design offers:

 

• Superior Strength: Enhanced resistance to bending and shearing forces, making them suitable for high-stress applications.
• Precise Preload Control: Critical for flange connections, where exact bolt length ensures proper preload to maintain a tight seal.
• Consistent Grip: Continuous threading guarantees uniform grip length, facilitating accurate torquing and secure flange alignment.

Key Benefits for Flange Connections

1. Corrosion Resistance: B8M and A194 8M excel in harsh environments, resisting pitting, crevice corrosion, and oxidation-even at high temperatures-ensuring long-term integrity and reducing downtime from fastener failure.
2. Load Distribution: Heavy hex nuts distribute clamping force evenly across the flange face, minimizing the risk of loosening or dislodgement under vibration or pressure fluctuations.
3. Durability in Extreme Conditions: Designed to withstand high pressure, temperature, and corrosive media (e.g., chlorides), making them reliable in industries like chemical processing, offshore oil, and marine engineering.

Summary

The full thread stud bolt with heavy hex nuts, made from ASTM A193 B8M and A194 8M stainless steel, is an optimal fastener for flange connections in high-pressure, corrosive environments. Its combination of continuous threading, robust material properties, and even load distribution ensures secure, leak-free performance, withstanding the rigors of industrial operations over time.

Stud Bolt Materials

The most common materials for stud bolts (for flanges) are ASTM A193 (grade B7, B8, B8M, B8T), ASTM A453 (grade 660), ASTM A320 (grade L7, L7M), and ASTM A182 (duplex and super duplex bolting). For aggressive fluids and environments, stud bolts can be coated with Xylan/PTFE, Zinc and other materials.

ASTM A193 Stud Bolts: Chemical Composition

Physical Element	ASTM A193 grade B7 (AISI 4140)	ASTM A193 grade B8 (AISI 304)	ASTM A193 grade 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	absent	8.0 - 11.0%	10.0 - 14.0%
Molybdenum	0.15 - 0.25%	absent	2.00 - 3.00%

ASTM A193 Stud Bolts: Mechanical Properties

ASTM A193	Size	Min Tensile Strength (KSI)	Min Yield Strength (KSI)	Min Elongation (%)	RA % min	Max HBW	Max HRC
ASTM A193 grade B7	Up to 2-1/2	125	105	16	50	321	35
	2-5/8 - 4	115	95	16	50
	4-1/8 - 7	100	75	18	50
ASTM A193 grade B8 Class 1	All	75	30	30	50	223	35
ASTM A193 grade B8M Class 1	All	75	30	30	50	223	96
ASTM A193 grade B8 Class 2	Up to 3/4	125	100	12	35	321	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
ASTM A193 grade B8M Class 2	Up to 3/4	110	95	15	45	321	35
	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

 

The material chosen for the threaded stud and the hex nuts should be compatible. Materials for bolting sets shall be selected based on the process's working temperatures, as shown in the table below:

	TEMPERATURE °C ( °F )
STUD BOLTS MATERIALS	MIN.	MAX.
CARBON STEEL	-29 (-20)	300 (572)
A193 B7, L7	-73 (-100)	400 (752)
A193 B6	0 (32)	500 (932)
A193 B8	-200 (-325)	575 (1067)
A193 B16	0 (32)	520 (968)
A193 B17B	-29 (-20)	650 (1202)
A913 Inconel 718	0 (32)	750 (1382)
A453 Gr. 660	-29 (20)	538 (1000)

 

ASTM A453 Stud Bolts for High-Temp. Service

ASTM A320 Stud Bolts for Low-Temp. Service

 

 Stud Bolts' Coating

Stud bolts can be coated to increase the resistance to corrosion. The most common types of coatings for stud bolts are listed below:

• Electro zinc plating
• Electro cadmium plating
• Hot dip galvanizing
• PTFE Coating
• Phosphate coating
• Electroless nickel plating
• Zinc-nickel coating
• Aluminum coating
• Silver coating
• Zinc/Nickel by electrodeposition
• Xylan coating

Products to our clients.

 

Our Superiority

Why choose Qishine?

High Quality: Qishine provide high quality products.
Reasonable and Competitive Price: Our products are sales well in oversea markets,especially in Europe, South America and Africa.
Professional Service: Qishine's sales team have rich experience in exporting and projects service.
Fast Delivery: Fast deliver the goods to all of the world.
One Stop Service: We provide gaskets,screws,flanges,pipes and fittings.Best choice for EPC companies and projects' construction.

Who choose Qishine?

Application:

 

FAQ

About Sample

 1.We can offer samples for testing,courier freight afforded by the receiver .

 2.For cost saving, freight prepaid is recommended.

 3.Special requirement accepted
 

About Order
 

1.Payment Term: T/T, L/C

2.Trade Term:  EXW, FCA, FOB, CFR,CIF,DDU

3.Documents: CI, PL, CO,MTC and BL.
 

About After Sale Service

Product Quality Guarantee: We guarantee our products quality for 12months from the date of BL.