Galvanized Hex Nut to GB/T 41 (Product Grade C, Class 4.0)

Thegalvanized hex nut to GB/T 41 is a product grade C hexagon nut in property class 4.0, manufactured in galvanized carbon steel. It is the standard matching nut for the GB/T 5780 hex bolt and is widely specified by domestic shipyards for cargo hold plates, brackets and light structural fixings in newbuilding projects.

What Is a GB/T 41 Hex Nut?

GB/T 41 specifies hexagon nuts of product grade C with a thread per the metric coarse-pitch system. Class 4.0 nut corresponds to a proof load rating that is compatible with class 4.8 bolts, meaning the nut strength is matched to the bolt for a complete and safe assembly. Grade C nuts have larger tolerances and are the economical commercial choice for general marine assembly work.

Marine Applications

Note: the following applications are based on typical industry practice for shipyard standard fixings; actual use should follow the vessel design documents.

Specifications & Materials

Why Choose sinofastener for Your Hex Nuts?

Standards Reference

• GB/T 41 – Hexagon nuts, product grade C
• GB/T 3098.2 – Mechanical properties of fasteners, nuts
• GB/T 193 – Metric coarse pitch threads
• GB/T 5267.1 – Electroplated coating, or GB/T 13912 – Hot dip galvanizing

FAQ

Why is class 4.0 nut used with 4.8 bolt?

A class 4.0 nut has sufficient proof stress to match a class 4.8 bolt, so the bolt remains the design-critical part. This is the standard pairing per GB/T 3098.2 for commercial grade C assemblies.

Can you supply galvanized nuts with different coatings?

Yes, we offer electroplated zinc per GB/T 5267.1 or hot-dip galvanized per GB/T 13912, depending on the corrosion requirement of your application.

Do you stock common hold sizes?

Yes, common sizes such as M12, M16 and M20 are available from stock or with short lead time based on your order quantity.