ASTM A193 B16 Bolt A194 7 Nut Valve Connection Fastener China Manufacturer

Product Description

Company Profile

ABOUT US

Xiamen Qishine Industry Co., Ltd. is a Chinese company established in 2013. We are a leading fabrication services provider in industries such as Oil & Gas, Petroleum, Marine, Oilfield, Mining, and Heavy Industry, specifically for pipeline construction and maintenance.

Qishine is ideal choice for EPC companies and project contractors. Our company specializes in supplying a range of products including Fasteners, Flanges, Gaskets, Fittings, Valves, Pipes and Piping Spare Parts. Our products are API, CE, TUV and ISO certified.   Products are widely used on oil rigs, new nuclear power plant, Chemical and Heavy Industry.

Qishine is proud as being a premium product supplier who works closely with our clients to achieve the best possible results. We have an experienced team, skilled labor force, and advanced facilities to ensure safe and efficient project completion, meeting deadlines and budget requirements.

Qishine is ideal choice for EPC companies and project contractors.

Product Description

Engineered for critical valve connection applications, our ASTM A193 B16 bolts and ASTM A194 7 nuts deliver unmatched reliability, corrosion resistance, and mechanical strength-ideal for demanding industrial environments where safety and performance non-negotiable.

 

Crafted from high-grade alloy steel, the ASTM A193 B16 bolts meet the strict standards of the American Society for Testing and Materials (ASTM), ensuring excellent tensile strength (minimum 120 ksi) and yield strength (minimum 105 ksi). Their heat-treated construction enhances durability, making them suitable for high-temperature (up to 1000°F/538°C) and high-pressure systems, common in oil & gas, petrochemical, power generation, and refining industries.

 

Paired perfectly with ASTM A194 7 nuts-made from carbon steel with a hot-dipped galvanized (HDG) finish-this fastener set offers superior corrosion protection against harsh elements, including moisture, chemicals, and industrial pollutants. The nuts' precision threading ensures a tight, vibration-resistant fit with the B16 bolts, eliminating leak risks in valve connections and reducing maintenance costs over time.

 

Designed for easy installation, our fasteners comply with global industry standards, compatible with most valve types (gate, globe, check valves) and flange connections. Each unit undergoes rigorous quality testing, including dimensional inspection, hardness testing, and corrosion resistance verification, to guarantee consistency and performance.

 

Whether you're upgrading existing systems or building new infrastructure, our ASTM A193 B16 bolts and ASTM A194 7 nuts provide the durability, compliance, and peace of mind your critical applications demand. Trust in fasteners that stand up to the toughest conditions-backed by our commitment to quality and customer satisfaction.

 

Certifications

 

As we know that Stud Bolts have many categories, the type for flange connection is called flange stud bolts, which has fully thread with chambered ends. The theoretical length is measured the thread. Continuous threaded stud bolt is very similar to it, except no chambered ends.



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