Square Head Bolts

1. What is a Square Head Bolt?

Square head bolts were one of the most commonly used fastening bolts before hex head bolts became widespread. These bolts consist of a threaded shaft with a distinctive square-shaped head instead of a hexagonal one. At Quang Thai, we manufacture and process square head bolts with strength grades ranging from 4.6 to 12.9, and diameters from M16 to M80.

 

2. Features of Square Head Bolts

Material

Quang Thai produces square head bolts with strength grades from 4.6 to 12.9 using various materials, including:

• Carbon Steel: C45, S45C, etc.
• Alloy Steel: SCM435, SS400, etc.
• Stainless Steel: A2-70, A4-70, SUS 304, SUS 316, etc.

Size Standards

Our square head bolts are manufactured according to JIS B 1182 - 1995, the Japanese Industrial Standard.

 

Surface Treatment

We offer various surface treatment options to enhance durability and corrosion resistance, including:

• Black Oxide Coating
• Hot-Dip Galvanizing
• Electroplated Zinc Coating

For high-strength bolts (10.9 grade and above), hot-dip galvanizing or electroplating is generally not recommended, as these processes involve hydrogen atoms that can reduce the bolt’s toughness and lead to cracking or fractures.

3. Applications of Square Head Bolts

Before hex head bolts became widely used, square head bolts were essential in various industries, from machinery installation to construction projects. Although hex head bolts are now more common, square head bolts are still preferred in specific applications:

 

• Restoration and Renovation Projects: Architects and contractors often choose square head bolts to maintain the historical authenticity and traditional aesthetic of older buildings.
• Machinery Manufacturing and Assembly: Both square and hex head bolts are widely used in machinery due to their strength and ease of installation. Engineers prefer square head bolts in tight spaces where visibility is limited.
• Furniture Assembly: Some furniture designs require square head bolts for aesthetic appeal and easy assembly. Many furniture manufacturers include square head bolts with their products, allowing customers to assemble them effortlessly.

4. Square Head Bolt Pricing

The price of square head bolts depends on several factors:

• Material: The cost varies based on the raw materials used.
• Standards: Different production standards have unique mechanical properties, strength grades, and material requirements, affecting pricing.
• Strength Grade: Higher strength grades come at a higher cost (e.g., Grade 8.8 > 6.6 > 4.6).
• Size: Larger diameters and longer bolts cost more (e.g., M42 is pricier than M39, and M20x120 is more expensive than M20x100).
• Surface Treatment: Coating options impact pricing for example, hot-dip galvanizing costs more than electroplated zinc.

 

Quang Thai is proud to be a leading manufacturer and distributor of square head bolts in southern Vietnam. We specialize in high-quality custom bolts and fastening materials at competitive prices. Our commitment to superior quality ensures customer satisfaction and reliability.

For more details or a consultation, call our hotline at +84 933 220 468. We look forward to serving you!