Carbon Steel 3-Hole Thread Insert

Carbon Steel Three-Hole Insert is a carbon steel threaded insert featuring three positioning holes. Compared with standard non-holed inserts, the evenly distributed holes allow the base material to locally deform and embed into the parent material during installation, creating stronger anti-rotation locking. Made from high-quality carbon steel, it forms high-strength, anti-rotation internal threads in soft materials like aluminum or plastic, effectively preventing loosening or shifting. It also provides a cost-effective solution for industrial assembly under vibration, offering both reinforcement and anti-rotation functionality.

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Product Features

Anti-rotation three-hole structure: Evenly spaced positioning holes improve interlocking with the base material, enhancing anti-torsion capability and preventing loosening or shifting.
High carbon steel material: Offers excellent mechanical strength and impact resistance, suitable for high-load connections.
Optional coating protection: Supports zinc, color zinc, and other coatings to improve corrosion resistance based on application needs.
Efficient and easy installation: Can be installed and positioned using dedicated tools without additional anti-rotation accessories, ensuring a simple and efficient process.

Applications

General Industrial Equipment: Thread reinforcement for indoor machinery such as machine tools and printing equipment.
Sheet Metal Processing: Thread connections in enclosures, cabinets, and sheet metal structures.
Heavy-Duty Furniture Assembly: Thread reinforcement for industrial racks and heavy office furniture.
Automotive Parts Manufacturing: Thread connections for automotive chassis and interior components.
Construction Machinery Components: Thread fastening for structural parts of small-scale construction machinery.

Product Specifications

307/308 type(three hole type) self-tapping screw sleeve. 308 is a reinforced version of 307, both of which are only in length. This product has three self-tapping circular grooves, is easy to assemble, has high-strength threads, and is shock-resistant. Suitable for: aluminum alloy, cast iron, soft steel.

307/308 type (three hole type)		307 Type	308 Type	External thread	Reference drilling diameter		Minimum drilling depth
The metric system	English system	Length	Length		Aluminum alloy	Cast iron	307 Type	308 Type
M3-0.5	U#4-40	4	6	M5-0.6	4.6-4.7	4.7-4.8	6	8
M4-0.7	U#8-32	6	8	M6.5-0.8	6.0-6.1	6.1-6.2	8	10
M5-0.8	U#10-24	7	10	M8-1.0	7.4-7.5	7.6-7.7	9	13
M6-1.0	U1/4-20	8	12	M10-1.25	9.3-9.4	9.5-9.6	10	15
M8-1.25	U5/16-18	9	14	M12-1.5	11.1-11.3	11.3-11.5	11	17
M10-1.5	U3/8-16	10	18	M14-1.5	13.1-13.3	13.3-13.5	13	22
M12-1.75	U7/16-14	12	22	M16-1.75	15.0-16.2	15.3-15.5	15	26
M14-2.0	U1/2-13	14	24	M18-2.0	17.0-17.2	17.3-17.5	17	28
M16-2.0	U5/8-11	14	24	M20-2.0	19.0-19.2	19.3-19.5	17	28

Company Profile

Dongtai Jinzhize Metal Products Co., Ltd.

Dongtai Jinzhize Metal Products Co., Ltd. is a specialized manufacturing facility dedicated to threaded connection products for the automotive and aerospace sectors. We primarily produce Helical Wire Inserts, Self-Tapping Inserts, Key Locking Inserts, Threaded Adapters, Oil Plugs, as well as matching installation taps and tools.

Established in 2015, the company operates from a 10,000-square-meter-owned manufacturing plant equipped with hundreds of machine tools and automated production systems. Through years of development, we have built an experienced team of design, development, and production specialists, complemented by a rigorous quality management system and comprehensive after-sales service mechanism.

Our products are widely utilized in the automotive industry (including engines and transmissions for both passenger and commercial vehicles), the aerospace industry, and rail vehicle manufacturing.

With an annual output value of 153 million RMB in 2024, we possess the capability for a large-scale, stable supply. We are committed to providing customers with highly consistent, traceable products and reliable service support.