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ASME/ANSI B18.2.1 (T1):1996 Square Head Bolt
ASME/ANSI B18.2.1 (T1):1996 Square Head Bolt uses a square head with a broad wrenching surface. It is suitable for inch-series joints involving low-speed heavy duty service, maintenance assembly, or a stronger gripping feel.
The square head can be located in slots, fixtures, or narrow structures, and in some cases its shape can help restrict rotation. Common uses include equipment bases, wood structures, traditional machinery, tooling fixtures, and maintenance replacement parts.
Compared with hex heads, the square head is better suited to specific tools or structural locating features. Head clearance, thread series, shank length, and surface protection should be confirmed to ensure assembly compatibility.
Dimensions unit: inch
|
Thread size d |
1/4 |
5/16 |
3/8 |
7/16 |
1/2 |
5/8 |
3/4 |
7/8 |
1 |
1-1/8 |
1-1/4 |
1-3/8 |
1-1/2 |
|
|
PP |
UNC |
20 |
18 |
16 |
14 |
13 |
11 |
10 |
9 |
8 |
7 |
7 |
6 |
6 |
|
ds |
Max. |
0.260 |
0.324 |
0.388 |
0.452 |
0.515 |
0.642 |
0.768 |
0.895 |
1.022 |
1.149 |
1.277 |
1.404 |
1.531 |
|
Min. |
0.237 |
0.298 |
0.360 |
0.421 |
0.482 |
0.605 |
0.729 |
0.852 |
0.976 |
1.098 |
1.223 |
1.345 |
1.470 |
|
|
s |
Nominal |
3/8 |
1/2 |
9/16 |
5/8 |
3/4 |
15/16 |
1-1/8 |
1-5/16 |
1-1/2 |
1-11/16 |
1-7/8 |
2-1/16 |
2-1/4 |
|
Max. |
0.375 |
0.500 |
0.562 |
0.625 |
0.750 |
0.938 |
1.125 |
1.312 |
1.500 |
1.688 |
1.875 |
2.062 |
2.250 |
|
|
Min. |
0.362 |
0.484 |
0.544 |
0.603 |
0.725 |
0.906 |
1.088 |
1.269 |
1.450 |
1.631 |
1.812 |
1.994 |
2.175 |
|
|
e |
Max. |
0.53 |
0.707 |
0.795 |
0.884 |
1.061 |
1.326 |
1.591 |
1.856 |
2.121 |
2.386 |
2.652 |
2.917 |
3.182 |
|
Min. |
0.498 |
0.665 |
0.747 |
0.828 |
0.995 |
1.244 |
1.494 |
1.742 |
1.991 |
2.239 |
2.489 |
2.738 |
2.986 |
|
|
k |
Nominal |
11/64 |
13/64 |
1/4 |
19/64 |
21/64 |
27/64 |
1/2 |
19/32 |
21/32 |
3/4 |
27/32 |
29/32 |
1 |
|
Max. |
0.188 |
0.220 |
0.268 |
0.316 |
0.348 |
0.444 |
0.524 |
0.620 |
0.684 |
0.780 |
0.876 |
0.940 |
1.036 |
|
|
Min. |
0.156 |
0.186 |
0.232 |
0.278 |
0.308 |
0.400 |
0.476 |
0.568 |
0.628 |
0.720 |
0.812 |
0.872 |
0.964 |
|
|
r |
Max. |
0.03 |
0.03 |
0.03 |
0.03 |
0.03 |
0.06 |
0.06 |
0.06 |
0.09 |
0.09 |
0.09 |
0.09 |
0.09 |
|
Min. |
0.01 |
0.01 |
0.01 |
0.01 |
0.01 |
0.02 |
0.02 |
0.02 |
0.03 |
0.03 |
0.03 |
0.03 |
0.03 |
|
|
b |
L≤6 |
0.750 |
0.875 |
1.000 |
1.125 |
1.250 |
1.500 |
1.750 |
2.000 |
2.250 |
2.500 |
2.750 |
3.000 |
3.250 |
|
L＞6 |
1.000 |
1.125 |
1.250 |
1.375 |
1.500 |
1.750 |
2.000 |
2.250 |
2.500 |
2.750 |
3.000 |
3.250 |
3.500 |
|
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FAQ
Frequently Asked Questions
-
1. How soon can I expect a reply after sending an inquiry?
A: We take every inquiry seriously. On working days, we will respond within 12 hours after receiving your inquiry.
-
2. What products do you mainly offer?
A: We focus on the production of fasteners made of carbon steel, stainless steel, and low-alloy steel. We are a direct manufacturer with independent production capacity. ASME/ANSI B18.2.1 (T1):1996 Square Head Bolt Factory. We own several fastener manufacturing facilities and have an international sales department, providing full-process services from production to export.
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3. Do you support customized production?
A: Customized production is our core business. We can develop and manufacture products based on the drawings or samples you provide.
-
4. Do you produce standard parts?
A: Yes. In addition to custom products, we also produce general construction machinery parts (GET parts) for equipment such as excavators, including bucket teeth, tooth holders, corner blades, pins, clips, bolts and nuts. ASME/ANSI B18.2.1 (T1):1996 Square Head Bolt Wholesale.
-
5. What is your production capacity?
A: We have 12 energy-efficient and environmentally friendly modern production lines (including one fully automatic shell molding line and four heat treatment lines), with an annual production capacity exceeding 20,000 tons, enabling us to steadily meet various order requirements.
-
6. What are your payment terms?
A: Trade terms (such as FOB, CIF, etc.) are confirmed when quoting. For batch production, we typically require a 30% deposit, with the balance paid against the copy of the bill of lading. T/T is the main payment method accepted, and L/C can also be negotiated.
-
7. How is the shipment arranged?
A: We are only 35 km away from Shanghai Port and Ningbo Port, so sea freight is the main mode of transportation, which is convenient and efficient. For urgent deliveries, we can also arrange air freight via Ningbo or Shanghai airports.
About Us
BETTER FASTENER INDUSTRY CO., LTD.
Better Fastener is a professional fastener enterprise specializing in the manufacturing of steel washers, stainless steel washers, spring washers and sealingwashers. Founded in 2001 as a washer factory, the company expanded into a comprehensive enterprise integrating washers, nuts, bolts, spring nuts and other fastener products in 2010. ASME/ANSI B18.2.1 (T1):1996 Square Head Bolt Suppliers in China.
The company positions itself as a provider of comprehensive one-stop services for customers, relying on technological R&D, industrial investment and trade distribution.
With an experienced professional team and a sound sales network, Better Fastener has achieved excellent sales performance in both domestic and foreign markets,and has grown into one of the competitive manufacturers and suppliers in China's industrial fastener industry.
Better Fastener is committed to becoming a trusted fastener supplier for customers with reliable product quality, reasonable prices and on-time deliveryCertification
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phone：+86-0571 85382212
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E-Mail：export@betterfastener.com
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