Wholesale Standard Bolts

Home / Products / Bolts
Product Category
Contact Us
SUBMIT

Carbon Steel Bolts Suppliers

Bolts (BOLTS) encompass a wide range of fasteners used for securing wood and metal structures, machinery, and concrete. Product types include hexagonal bolts, heavy-duty structural bolts, round head bolts, wood screws, U-bolts, eyebolts, and more. Available in a variety of finishes, including galvanized, stainless steel, hot-dip galvanized, and black oxide, they meet the durability and corrosion resistance requirements of diverse environments.

These bolts are suitable for general-purpose connections and high-strength applications. Whether used in industrial equipment, building framing, agricultural machinery, or installation projects, this series of products provides secure connections and long-lasting performance.

About Us

Established in 2004, JIAXING SINI FASTENER CO., LTD. has over 20 years of experience in the fastener field. We are a well-known leading exporter of bolts and screws. Our specialization lies in supplying both standard and custom-engineered bolts and screws. Carbon Steel Bolts Suppliers and Wholesale Standard Bolts Factory.


In addition to manufacturing products that meet DIN and IFI standards, SINI FASTENER also has the capability to produce according to customer-specific designs and drawings. Most items are available in steel and stainless steel, and can be provided in both inch and metric sizes.
•    Bolts: Manufactured in diameters from 3/16” to 1 1/2” (5mm–52mm) and lengths from 1/2” to 60” (10mm–1500mm). Our most competitive products include carriage bolts and round head bolts.
•    Screws: Produced in diameters from #4 to 1/2” (3.5mm–12mm) and lengths from 1/2” to 60” (10mm–1500mm). Our key advantage lies in corrosion-resistant construction screws.      


With production facilities located in Haiyan, Zhejiang and Lianyungang, Jiangsu, we serve customers across North America, South America, and Europe. Our diverse client base spans industries such as construction hardware, machinery, machine tools, electrical appliances, and furniture. Wholesale Custom Non-Standard Bolts.
SINI FASTENER is ISO 9001 certified, ensuring consistent quality and reliability.

Jiaxing Sini Fastener Co., Ltd.

Certificate

Latest Updates

Industry Knowledge

Carbon Steel Bolts: Engineered for Demanding Connections

Jiaxing Sini Fastener Co., Ltd. is a Carbon Steel Bolts manufacturer based in China, with over 20 years of experience in the fastener industry. We specialize in producing standard and custom-engineered carbon steel bolts that meet DIN, IFI, and customer-specific requirements. Our bolts are used in construction, machinery, agricultural equipment, and infrastructure projects worldwide.

Our product range includes timber bolts, carriage bolts, silo bolts, plow bolts, elevator bolts, hex bolts, heavy hex bolts, and A394 hex tower bolts, supplied both as Wholesale Standard Bolts to catalog specification and, through our Non-Standard Bolts Factory, to a customer's own drawing. We manufacture in diameters from 3/16” to 1 1/2” (5mm–52mm) and lengths up to 60” (1500mm), with most items available in both inch and metric sizes.

Product Range and Application Fit

We supply a comprehensive selection of carbon steel bolts, each designed for specific applications and industries. The table below outlines our main bolt types, their typical applications, and key specifications.

Bolt Type Typical Applications Key Specifications
Timber Bolts Marine and wood construction, docks, bridges A307 Grade A, sizes 1/2"–1 1/2", lengths up to 96", plain or HDG
Carriage Bolts Wood connections, furniture, fencing ASME B18.5, DIN603, ISO8677; grades A307, SAE J429 GR2/5/8, 4.8/8.8; sizes 1/4"–7/8" (M6–M24)
Silo Bolts Grain silos, cement tanks, feed bins, sheet metal structures Carbon steel, grades 8.8/10.9, M12/M16, lengths 30–300mm, zinc-plated, plastic cap, sealing washer
Plow Bolts Agricultural machinery, earthmoving equipment Carbon steel, various grades, sizes and lengths customized
Elevator Bolts Conveyor systems, bucket elevators, material handling Carbon steel, flat countersunk head, square neck, various sizes
Hex Bolts & Screws General industrial, machinery, structural steel DIN, IFI standards; grades 4.8, 8.8, 10.9, 12.9; sizes M5–M52
Heavy Hex Bolts Structural steel connections, bridges, heavy machinery ASTM A325, A490; sizes 1/2"–1 1/2"
A394 Hex Tower Bolts Transmission towers, telecommunication structures ASTM A394, sizes 1/2"–1 1/2", hot-dip galvanized

Materials and Finishes

Our carbon steel bolts are manufactured from high-quality carbon steel and are available in various grades to meet specific strength requirements. Common grades include 4.8, 8.8, 10.9, and 12.9, as well as ASTM A307, A325, A394, and SAE J429 grades. We also offer stainless steel options for enhanced corrosion resistance.

To suit different environments, we provide multiple surface finishes:

  • Plain: Suitable for indoor or dry applications.
  • Zinc Plated: Provides moderate corrosion resistance for general use.
  • Hot-Dip Galvanized (HDG): Offers superior corrosion protection for outdoor and harsh environments.
  • Black Oxide: Aesthetic finish with mild corrosion resistance.
  • Mechanical Galvanization and Dacromet: For specialized applications requiring high corrosion resistance without hydrogen embrittlement.

Critical Specifications and Customization

We understand that each project has unique requirements. Our engineering team works closely with customers to define critical specifications such as diameter, length, thread pitch, head type, neck type, grade, and coating. We can produce bolts according to customer drawings or samples, ensuring a perfect fit for the application.

Key specification parameters we consider include:

  • Diameter and Length: From 3/16” to 1 1/2” (5mm–52mm) diameter and up to 60” (1500mm) length.
  • Thread: Metric or inch threads, coarse or fine pitch.
  • Head Type: Hex, round, flat, dome, countersunk, etc.
  • Neck Type: Square, finned, or smooth.
  • Grade: Determined by load requirements and environmental conditions.
  • Coating: Selected based on corrosion exposure and aesthetic needs.

Quality Assurance and Testing

Quality is integral to our manufacturing process. We are ISO 9001 certified and conduct inspections at every stage of production. Our in-house testing laboratory is equipped with:

  • Salt Spray Test Chamber for corrosion resistance evaluation.
  • Universal Testing Machine (UTM) for tensile and proof load testing.
  • Hardness Tester for material hardness verification.
  • Video Measuring System (VMS) for dimensional accuracy.
  • Metallographic Microscope for microstructure analysis.
  • Optical Emission Spectrometer (OES) for chemical composition analysis.

For finished products, we perform comprehensive inspections based on customer requirements and international standards. We can provide test reports and certificates of compliance as needed.

Installation and Maintenance

Proper installation ensures the performance and longevity of carbon steel bolts. We recommend using calibrated torque wrenches and following the specified torque values for each bolt grade and size. For bolts with sealing washers, ensure the washer is correctly seated to prevent leakage. Regular inspection for signs of corrosion or loosening is advised, especially in outdoor or high-vibration applications.

Our bolts are designed for ease of maintenance. In case of replacement, simply match the original specifications. We can provide technical guidance on installation and maintenance upon request.

Information We Use to Configure Your Solution

To prepare an accurate quotation and ensure the bolts meet your project needs, we require the following information:

  • Bolt type and standard (e.g., hex bolt DIN933, carriage bolt ASME B18.5).
  • Material and grade (e.g., carbon steel 8.8, stainless steel 304).
  • Dimensions: diameter, length, thread pitch.
  • Head and neck type.
  • Surface finish (e.g., HDG, zinc plated).
  • Quantity required.
  • Any special requirements (e.g., custom markings, packaging).

Providing detailed drawings or samples helps us deliver exactly what you need. Our team responds to inquiries within 12 hours on weekdays.

Frequently Asked Questions

What is the difference between timber bolts and carriage bolts?

Timber bolts, also known as dome head bolts, have a large rounded head with fins under the head to prevent rotation in wood. They are commonly used in marine and heavy wood construction. Carriage bolts have a round head with a square neck that seats into wood to prevent turning. They are used in general wood connections and are available in a wider range of sizes.

Can you produce bolts according to our drawings?

Yes, we specialize in custom-engineered bolts. We can manufacture according to your drawings or samples, ensuring exact specifications and fit. Our engineering team will review your requirements and provide a proposal.

What is the typical lead time for an order?

Lead time depends on order quantity, complexity, and material availability. We will provide a specific lead time upon receipt of your inquiry and order details.

Do you provide test certificates?

Yes, we can provide test reports and certificates of compliance based on customer requirements and international standards. Our in-house testing laboratory ensures that every batch meets the specified quality criteria.

What are the main applications of your carbon steel bolts?

Our carbon steel bolts are widely used in construction, machinery, agricultural equipment, marine structures, transmission towers, and material handling systems. They are suitable for both general-purpose and high-strength connections.

How do you ensure product quality?

We conduct inspections after each production process and perform comprehensive final inspections. Our quality control laboratory is equipped with advanced testing equipment, and we are ISO 9001 certified. We also welcome third-party inspections.