Product instruction
A193 B7 Stud Bolt is a bolt with threads on both ends that designed to be screwed into a fixed part at one end, and to receive a nut on the other end. In Petroleum or Chemical industry, they are prominently used for flange connection, so stud bolt used with two nuts on either side is the most common combination which replaces bolt and nut assembly.
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
Q:How can I place order?
A: You can contact us by email or social media like WhatsApp on the order detail or place order on line.
Q:How about the payment?
A: For new clients, advance payment(30%-100% of total amount) is required, the balance need to be paid before the delivery after your inspection.
Q:How can I pay you?
A: By T/T (Telegraphic Transfer) or L/C (Letter of Credit). After you receive the PI, you can make the payment through your bank as per the terms mentioned in PI.
Q: What's the order procedure?
A: First we discuss order details, production details by email ,TM or other social media; then we issue you an PI for your confirmation. You will be requested to make full payment or deposit before we go into production.After we get the deposit, we start to process the order. Depending on the products you order, we usually a couple of days or even moths to complete production if we don't have the items in stock. Before production has been finished, we will contact you for shipment details, and the balance payment. After payment has been settled, we shall arrange the shipment for you.
Q: How do you deal with defective products received by the clients?
A: If there are some defective items, we usually credit to our customer or replace them in next shipment.
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