Flange Nut

Carbon Steel Hex Flange bolt

Carbon Steel Hex Flange bolt provide a secure and tight fit, while also preventing the nut from loosening due to vibration. This is especially important in industries where machinery and other heavy equipment are used, as any loosening of fittings can cause dangerous and costly consequences. The flange of Carbon Steel Hex Flange bolt acts as a washer, providing additional support while preventing the nut from embedding itself into the surface of the material being fastened. This greatly reduces the risk of damage to the structure, as well as providing a more aesthetically pleasing finish.

Carbon Steel Hex Flange bolt provide a secure and tight fit, while also preventing the nut from loosening due to vibration. This is especially important in industries where machinery and other heavy equipment are used, as any loosening of fittings can cause dangerous and costly consequences. The flange of Carbon Steel Hex Flange bolt acts as a washer, providing additional support while preventing the nut from embedding itself into the surface of the material being fastened. This greatly reduces the risk of damage to the structure, as well as providing a more aesthetically pleasing finish.

Product Details

Product Introduction
Carbon steel hexagon flange bolts with a serrated bearing face under the head. The integrated circular flange acts as a captive washer, while the serrations embed into the mating surface to create a mechanical lock that resists vibration-induced loosening. Sizes M5 through M20 are supplied in metric coarse thread; property classes 8.8, 10.9, and 12.9 per ISO 898-1. Suitable for use with standard hex nuts or directly in tapped assemblies.

Material & Mechanical Properties
Forged from medium carbon steel and quench-and-tempered to achieve the specified tensile and proof load values. Mechanical certification is provided by lot, traceable to heat number. Classes 8.8 and 10.9 cover general high-strength bolting; class 12.9 is specified where tensile strength exceeding 1200 MPa is required. The carbon steel substrate delivers the toughness needed for dynamic and impact-loaded joints.

Geometry & Thread
Hexagonal wrenching head dimensioned to standard DIN/ISO wrench sizes. The flange underside carries annular serrations that bite into the mating surface during tightening, generating prevailing-torque resistance to rotation. Flange diameter distributes clamp load and prevents the fastener head from embedding in softer structural materials. Metric coarse pitch thread to ISO 724 allows rapid assembly and resists stripping.

Corrosion Protection
Zinc electroplated per ASTM B633 (Fe/Zn 5–8 µm) with clear passivation as standard, offering reliable corrosion resistance for indoor and sheltered outdoor environments. For exposed structural applications and higher corrosivity categories, zinc-nickel, zinc flake, or hot-dip galvanized finishes are applied. Coating selection considers hydrogen embrittlement limits for each property class.

Application Suitability
Heavy machinery, engine and chassis components, conveyor systems, and industrial equipment where vibration-induced loosening risks joint integrity. The serrated flange design eliminates the need for separate locking washers or threadlocking compounds, reducing part count and assembly time. Compatible with hex nuts of matching property class and with tapped holes in steel and cast iron.

Technical Parameters

Place of Origin CHINA
Standard Carbon Steel Hex Flange bolt
HS CODE 7318160000
Brand Name QBH
Certification ISO9001
Material 35K, 40Cr, 35CrMo, SCM435, etc.
Size M3-M90
Production Process Cold forging and hot forging
Class 4.8/ 6.8/ 8.8/ 10.9/ 12.9
Delivery Time Within 30 Days

Product Introduction
Carbon steel hexagon flange bolts with a serrated bearing face under the head. The integrated circular flange acts as a captive washer, while the serrations embed into the mating surface to create a mechanical lock that resists vibration-induced loosening. Sizes M5 through M20 are supplied in metric coarse thread; property classes 8.8, 10.9, and 12.9 per ISO 898-1. Suitable for use with standard hex nuts or directly in tapped assemblies.

Material & Mechanical Properties
Forged from medium carbon steel and quench-and-tempered to achieve the specified tensile and proof load values. Mechanical certification is provided by lot, traceable to heat number. Classes 8.8 and 10.9 cover general high-strength bolting; class 12.9 is specified where tensile strength exceeding 1200 MPa is required. The carbon steel substrate delivers the toughness needed for dynamic and impact-loaded joints.

Geometry & Thread
Hexagonal wrenching head dimensioned to standard DIN/ISO wrench sizes. The flange underside carries annular serrations that bite into the mating surface during tightening, generating prevailing-torque resistance to rotation. Flange diameter distributes clamp load and prevents the fastener head from embedding in softer structural materials. Metric coarse pitch thread to ISO 724 allows rapid assembly and resists stripping.

Corrosion Protection
Zinc electroplated per ASTM B633 (Fe/Zn 5–8 µm) with clear passivation as standard, offering reliable corrosion resistance for indoor and sheltered outdoor environments. For exposed structural applications and higher corrosivity categories, zinc-nickel, zinc flake, or hot-dip galvanized finishes are applied. Coating selection considers hydrogen embrittlement limits for each property class.

Application Suitability
Heavy machinery, engine and chassis components, conveyor systems, and industrial equipment where vibration-induced loosening risks joint integrity. The serrated flange design eliminates the need for separate locking washers or threadlocking compounds, reducing part count and assembly time. Compatible with hex nuts of matching property class and with tapped holes in steel and cast iron.

Technical Parameters

Place of Origin CHINA
Standard Carbon Steel Hex Flange bolt
HS CODE 7318160000
Brand Name QBH
Certification ISO9001
Material 35K, 40Cr, 35CrMo, SCM435, etc.
Size M3-M90
Production Process Cold forging and hot forging
Class 4.8/ 6.8/ 8.8/ 10.9/ 12.9
Delivery Time Within 30 Days
FAQ

1. How do you let me trust you.

Jiaxing City Qunbang Hardware Co.,ltd hs its own right of import and export,QBH trademark in China,United States,European Union have been registered.At the same time,you can also check the registration information of our company in the China industry and Commerce system.

 

2. How about your price.

We will be based on different markets,for different quality and quantity,tailor-made prices for customers,in order to achieve win-win goal.

 

3. How do you control your quality.

Incoming quality contral( IQC)→Process Quality control(PQC)→Output quality control(OQC),and the random samples is sent to TUV for testing.If the customer received the goods and found quality problems,QBH company promises to be responsible for returning money or replenishing the goods

 

4. Could you provide free samples?

For new customer, We can provide free samples for standard fastener, But the clients will pay the express

charges. For old customer, We will send you free samples and pay express charges by ourself.

 

5. What is your packing.

Usually 25KG/carbon,36CTNS on the pallets,or 20-30kg/Bags,then on the pallet,QBH company personalized packagingis also available,like 10PCS/plastic bag or 10pcs/box,it can print some information

such as LOGO and pattern of customers.

 

6. What is your payment term

Normally,our terms of payment are TT and L/C,if we cooperate for a long time,we can reach the point of mutual trust,and fully support our customers to become bigger and stronger in the local market.Not only in the price concessions,but also in the payment can also be made on credit,Specific credit sales time needs to be negotiated separately.

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