Stainless Steel 304 Stud Bolts

Stainless Steel 304 Stud Bolts are threaded fasteners made from the most common grade of austenitic Stainless Steel. Grade 304 has 18-20% of chromium and 8-10.5% of nickel and provides good corrosion resistance and good tensile strength in a wide range of environments. These studs are suitable for use in flanged pipe joints, pressure vessels, and structural assemblies. These are suitable for use in the chemical, food processing, petrochemical, and marine industries. Available in inch and metric sizes, they come paired with ASTM A194 Grade 8 nuts for a matched fastener assembly.

Approx Price Range

The approximate price range of Stainless Steel 304 stud bolts per kg and the factors that affect their cost are explained below.

Price Per Unit / Kg

Pricing for ASTM A193 B8 stud bolts is generally Rs 70–95. Smaller diameters may be priced per piece. The table below gives a general guide.

Factors Affecting Price

Size, order quantity, raw material rates, grade certification, surface finish, and thread type all affect the price of SS 304 stud bolts.

Types of SS 304 Stud Bolts

SS 304 stud bolts are available in several configurations depending on joint design and application. Here are the most common types.

Fully Threaded Stud Bolts

Double-End Stud Bolts

Tap-End Stud Bolts

Collar Stud Bolts

Eye Bolt Studs

Specifications of Stainless Steel 304 Stud Bolts

The table below covers the key specification standards that govern ASTM A193 Grade B8 stud bolts.

Parameter	Details
Material Standard	ASTM A193 / ASME SA193
Grade	B8 (Class 1 and Class 2)
Nut Standard	ASTM A194 Grade 8
Thread Type	UNC, UNF, Metric
Length	25 mm to 3000 mm (custom available)
Diameter Range	M6 to M100 / 1/4" to 4"
Finish	Plain, Passivated, Electropolished

Chemical Properties of Stainless Steel 304 Stud Bolts

The table below shows the chemical composition of grade 304 stainless steel as per ASTM A193.

Element	Min (%)	Max (%)
Carbon (C)	-	0.08
Manganese (Mn)	-	2.00
Phosphorus (P)	-	0.045
Sulphur (S)	-	0.030
Silicon (Si)	-	0.75
Chromium (Cr)	18.00	20.00
Nickel (Ni)	8.00	10.50
Nitrogen (N)	-	0.10
Iron (Fe)	Balance	-

Mechanical Properties of Stainless Steel 304 Stud Bolts

The table below lists the mechanical properties for ASTM A193 B8 (Class 1) and B8 (Class 2) stud bolts.

Property	Class 1	Class 2
Tensile Strength	515 MPa (75 ksi) min	690 MPa (100 ksi) min
Yield Strength (0.2% offset)	205 MPa (30 ksi) min	450 MPa (65 ksi) min
Elongation	30% min	20% min
Reduction of Area	50% min	45% min
Hardness (Brinell)	223 HBW max	321 HBW max

Physical Properties of Stainless Steel 304 Stud Bolts

These are the standard physical properties of the 304 base material used in stud bolt manufacture.

Property	Value
Density	7.93 g/cm³
Melting Point	1400 – 1455°C
Modulus of Elasticity	193 GPa
Thermal Conductivity	16.2 W/m.K at 100°C
Electrical Resistivity	0.72 µΩ.m
Magnetic Permeability	Non-magnetic (annealed state)
Specific Heat Capacity	500 J/kg.K

Dimension Chart of SS 304 Stud Bolts

The table below provides standard dimensions for SS 304 stud bolts per ASME B16.5.

Diameter	Diameter in inches	Diameter in mm	Nut Sizes
M12	0.4724	12	19
M18	0.7087	18	27
M16	0.6299	16	24
M20	0.7874	20	30
M10	0.3937	10	17
M14	0.5512	14	22
M24	0.9449	24	36
M48	1.8898	48	75
M33	1.2992	33	50
M30	1.1811	30	46
M36	1.4173	36	55
M22	0.8661	22	32
M27	1.063	27	41
M42	1.6535	42	65
M39	1.5354	39	60
M45	1.7717	45	70
M56	2.2047	56	85
M64	2.5197	64	95
M60	2.3622	60	90
M52	2.0472	52	80
M68	2.6772	68	100
M76	2.9921	76	110
M72	2.8346	72	105
M80	3.1496	80	115
M90	3.5433	90	130

Size Chart of Stainless Steel 304 Stud Bolts

The chart below covers metric sizes available from standard suppliers, including thread pitch and approximate weight per piece.

Dia	-	M3	M4	M5	M6	M8
Nom	4.50	5.50	6.50	7.50	9.00
Max	4.30	5.30	6.30	7.30	8.80
Min	4.70	5.70	6.70	7.70	9.20
Nom	0.60	0.65	0.75	0.75	0.75
Max	0.52	0.57	0.67	0.67	0.67
Min	0.68	0.73	0.83	0.83	0.83
Nom	0.55	0.55	0.80	0.80	0.85
Max	0.50	0.50	0.75	0.75	0.80
Min	0.60	0.60	0.85	0.85	0.90
Max	1.40	1.40	1.40	1.40	1.40
Min	0.70	0.70	0.70	0.70	0.80

Torque Chart of Stainless Steel 304 Stud Bolts

Use the torque values below as a starting guide. Always refer to the equipment manufacturer's recommendation for final assembly.

Size
-	Dwg/No.	Bolt Size	1st	2nd	Final
1/2″	4-bolt	1/2″	10	20	30
2-1/2″	4-bolt	5/8″	40	80	120
3-1/2″	8-bolt	5/8″	40	80	120
5″	8-bolt	3/4″	60	120	200
2″	4-bolt	5/8″	40	80	120
3″	4-bolt	5/8″	40	80	120
18″	16-bolt	1-1/8″	213	426	710
1″	4-bolt	1/2″	15	30	50
1-1/2″	4-bolt	1/2″	20	40	60
3/4″	4-bolt	1/2″	13	27	40
20″	20-bolt	1-1/8″	213	426	710
24″	20-bolt	1-1/4″	300	600	1,000
1-1/4″	4-bolt	1/2″	20	40	60
6″	8-bolt	3/4″	60	120	200
12″	12-bolt	7/8″	95	190	320
14″	12-bolt	1″	147	294	490
8″	8-bolt	3/4″	60	120	200
4″	8-bolt	5/8″	40	80	120
10″	12-bolt	7/8″	95	190	320
16″	16-bolt	1″	147	294	490

Key Features of Stainless Steel 304 Stud Bolts

The features given below make ASTM A193 B8 304 stud bolts a common choice for many industries.

18-20% chromium and 8-10.5% nickel content

Available in Class 1 (solution treated) and Class 2 (strain hardened)

Non-magnetic in the annealed state

Serviceable from -196°C to 870°C in intermittent service.

Compliant with ASTM A193 / ASME SA193

Paired with ASTM A194 Grade 8 nuts

Available in plain, passivated, and electropolished finishes

Good resistance to oxidising environments, dilute acids, and alkaline media.

Applications of Stainless Steel 304 Stud Bolts

ASTM A193 B8 stud bolts are used across a wide range of industries and process environments.

Chemical processing plants
Food and beverage industry

Pharmaceutical equipment

Water treatment facilities

Marine and offshore structures

Pulp and paper mills

Power generation

Dairy and beverage processing

How to Choose the Right SS 304 Stud Bolt Supplier?

Consider the following things when choosing the correct SS 304 bolt supplier.

Supplier Selection Criteria

Select a supplier that holds ASTM A193 Grade B8 certified material and can issue Mill Test Certificates with every order. A dependable supplier should provide dimensional traceability, predictable lead times, and Class 1 & Class 2 options.

Technical Considerations

Determine the thread standard (UNC or metric) and whether Class 1 or Class 2 properties are needed for the application. If pressure-rated flanges are used, the studs shall be tested and certified to the proper pressure class. Nut grade must always match stud grade. B8 studs require ASTM A194 Grade 8 nuts.

Quality and Certification Check

Request for NABL-accredited lab test reports or third-party inspection certificates. Check for ASTM A193, ASME SA193, and ISO compliance. Material certification according to EN 10204 3.1 or 3.2 shall be requested for export or EPC projects.

Procurement Tips for Bulk Orders

If you want a greater quantity, ask for a quote per kilogram, as generally the greater quantity you buy, the less you will pay per kilogram. Specify the surface finish on the purchase order. If the project is for export, verify that the supplier can provide country-of-origin documentation and appropriate export packaging.