HEX BOLTS

The products are strictly conform with DIN, ISO, ASTM, ANSI, BS, JIS...

● Level: A325/A325M/A490/A490M/8.8 /10.9/12.9/Gr5/Gr8

● Coating: Plain/Black/Galvanized/H.D.G /YZP/Dacromet/Xylan

ASTM B7/B7M

THREAD RODS

The longest can reach 3.66 meters(12FT)

China Professional Metal Fasteners

Manufacturer and Supplier with Over 20 Years of Experience

Bolt

Head shape: Hexagonal head, square head, round head can all be produced.
Size: M4-M100, 3/8 "-4"...

Nut

Type: hex nut, cap nut, couple nut, lock nut, spring nut
Size: M4-M100, 3/8'-4' is divided...

Washer

Type: Flat washer, spring washer
Specifications: M3-M100, 1/4

Threaded Rod

Size: M4-M100, 3/8 "-4", divided into metric size and inch size
Thread type: Full Thread

Precast Accessories

Size: Customization based on drawings or samples, both metric size and inch size are available

Custom Fasteners

Size: Customization based on drawings or samples, both metric size and inch size are available

About Material

Carbon steel, alloy steel, stainless steel are all acceptable.
According to customer requirements

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Topbolt - Best Standard Bolts and Nuts for Your Industries

The products are applied to architectural steel structures, brigdes, oil, pipeline, machinery equipment, furniture, vessel, railway.

Bridge
Industry
Ship
Solar Power
Steel Structural

Why Choose Topbolt for Your Projects?

Trusted Supplier of Bolts, Nuts, and Fasteners Conforming to DIN, ANSI/IFI, JIS, BS, ISO, and GB Specifications.

Ningbo Topbolt Metalworks Co., Ltd. is a manufacturer in China which mainly produces high strength fasteners and specializes in all kinds of hardwares. Founded in 2001, In the past few years, it developed fast with its factory located in Ningbo Zhenhai Chemical industrial area and its headquarter /foreign sales department in Ningbo Jiangdong Eastern Business Centre.

The factory now covers an area of approximately 15,000 square meters, with monthly production capacity of 2000 tons. The company has its all-around research system, supply management, large-scale warehouse...

Founded In

㎡

Covers an Area

Monthly Production Capacity

million

Annual Sales

DIGITAL SHOWROOM

If you want to learn more about our manufacturing capabilities, you can click on the avatar in the scene, or accept my invitation!

What Makes Topbolt Fasteners Manufacturing Stand Out?

Material Science

Carbon steel, alloy steel, stainless steel, Special material customization
Direct procurement from raw material factories, discounted prices, and sufficient stock availability

Standard

Strictly produce according to standard dimensions such as DIN, ISO, GB, JIS, ASTM, SAE, ASME, etc

Services

Accept customized production (including sample processing, drawing processing), OEM production

Topbolt News & Fasteners Knowledge Center

DIN938 Stud Bolt Full Sizing, Matching & Application Guide

2026-07-09

1. IntroductionDIN 938 is a standard German double-end stud bolt (latest DIN 938:2025), widely used for steel machine tools, hydraulic flanges, pump valves and mechanical assembly. DIN938 Stud Bolt features a fixed 1d tap-in thread length exclusively designed for steel tapped holes. Mixing DIN938 wi

2026-07-09

A194 2H Nut Matching Rules For A193 B7 Stud Bolts

2026-07-08

1. IntroductionA193 Grade B7 Thread Rods are the mainstream high-strength fasteners for high-temperature, high-pressure, pipeline flange and pressure vessel equipment. Improper nut matching is the main cause of thread slipping, galling, preload loss and flange leakage in overseas projects.As specifi

2026-07-08

Matching Nut & Washer Rules For ASTM A325 & A490 Heavy Hex Structural Bolts

2026-07-07

1. IntroductionASTM A325 and A490 heavy hex structural bolts are the core high-strength fasteners for North American steel structures, building frames and bridge construction. Most buyers only focus on bolt grades but ignore the matching rules for nuts and washers.Mismatched low-grade accessories wi

2026-07-07

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We welcome all of you from all over the world to join us for the win-win business partnership and friendship, welcome to China, welcome to Ningbo Topbolt!

China Professional Metal Fasteners

Topbolt - Best Standard Bolts and Nuts for Your Industries

Why Choose Topbolt for Your Projects?

DIGITAL SHOWROOM

DIN938 Stud Bolt Full Sizing, Matching & Application Guide

A194 2H Nut Matching Rules For A193 B7 Stud Bolts

Matching Nut & Washer Rules For ASTM A325 & A490 Heavy Hex Structural Bolts

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