Hexagonal bolts

Hexagonal bolts are hexagonal head bolts (partially threaded) - Grade C and hexagonal head bolts (fully threaded) - Grade C. Also known as hexagonal head bolts (rough), hexagonal head bolts and black iron screws.

Commonly used standards can be found: SH3404, HG20613, HG20634, etc.

Hexagonal bolt: A type of fastener consisting of a head and a screw (a cylinder with external threads). It needs to be matched with a nut and is used to fasten two parts with through holes.

This type of connection is called a bolt connection. If the nut is unscrewed from the bolt, the two parts can be separated, so the bolt connection is a detachable connection.

Almost all sizes are in stock. Fast delivery and shipped in bulk. If necessary, we can produce and customize bolts of various specifications overnight.

The performance grades of bolts for steel structure connections are divided into more than 10 grades, including 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, and 12.9. Among them, bolts of grade 8.8 and above are made of low carbon alloy steel or medium carbon steel and have been heat treated. (quenching, tempering), commonly known as high-strength bolts, and the others are commonly known as ordinary bolts. The bolt performance grade label consists of two parts of numbers, which represent the nominal tensile strength value and the yield strength ratio of the bolt material. For example:

The meaning of bolts with performance level 4.6 is:

1. The nominal tensile strength of the bolt material reaches 400MPa;

2. The yield-to-strength ratio of the bolt material is 0.6;

3. The nominal yield strength of the bolt material reaches 400×0.6=240MPa levelPerformance level 10.9 high-strength bolts, after heat treatment, can achieve:

1. The nominal tensile strength of the bolt material reaches 1000MPa;

2. The yield-to-strength ratio of the bolt material is 0.9;

3. The nominal yield strength of the bolt material reaches 1000×0.9=900MPa level

The meaning of bolt performance grade is an internationally accepted standard. Bolts with the same performance grade have the same performance regardless of the difference in material and origin. Only the performance grade can be selected for design.

The so-called strength levels of 8.8 and 10.9 refer to the shear stress resistance levels of bolts of 8.8GPa and 10.9GPa‌

‌Material Selection‌: The materials of hexagonal bolts usually include mild steel, medium carbon steel and alloy steel. Low carbon steel, such as 1008, 1015, 1018, etc., is commonly used in products without hardness requirements such as grade 4.8 bolts, grade 4 nuts, and small screws. Alloy steel adds alloy elements to plain carbon steel, such as SCM435 chromium-molybdenum alloy steel, to improve the special properties of the steel.

‌Production process‌:

‌Pickling‌: Immerse the entire disk unit in a hydrochloric acid bath at room temperature and with a concentration of 20-25% to remove the oxide film on the surface of the wire.

‌Cold drawing‌: The disc element is cold drawn to the required wire diameter through a wire drawing machine. It is suitable for wires used in large screws, nuts, and threaded rods.

‌Cut‌: Cut the wire into the required length or thickness with movable scissors.

‌Forging‌: The wire rod is cold forged or hot forged to achieve the shape and length (or thickness) of the semi-finished product.

‌Surface treatment‌: In order to prevent corrosion and increase lubricity, surface treatment includes pickling, film treatment and lubricant treatment. Pickling removes the oxide film, the film treatment forms insoluble compounds on the steel surface, and the lubricant increases the lubrication performance during processing.

‌Quality Inspection‌: During the production process, hardness, appearance, etc. need to be tested to ensure product quality. For example, the hardness of wires made of 1018 and 1022 is HV120-170 after annealing.

Applications: Designed for specialized applications requiring unique specifications.

Installation method: Customized installation according to specific application requirements.

Benefits: Customized specifications to meet unique project needs, ensuring optimal performance.

Custom Sizes: We offer bolts in standard and custom sizes to meet specific project requirements. Our advanced processing capabilities ensure a perfect fit for your application.

Material Selection: Depending on the application and environmental conditions, we offer hex bolts made of stainless steel, galvanized steel, carbon steel and other specialty materials.

Surface Treatments: For enhanced corrosion resistance and durability, we offer a variety of surface treatments including galvanized, galvanized and custom coatings.