A quick guide about different nut bolts and important buying tips

A quick guide about different nut bolts and important buying tips

Nuts and bolts are the basic components used in various types of machinery. A bolt is sometimes called a threaded screw and is often paired with a nut. In order to fit together, both the nut and bolt should be of the same size. Besides, the bolt type, its physical dimensions, thread density, and tightening are a few important characteristics that are crucial for proper bolt installation.

If you are working on a particular project that requires nut bolts, then considering a few selection tips is essential for effective installation. But before going through the buying tips, let us first gain a basic understanding of types of bolts based on the material, finish, size, and thread type.

Types of bolts based on materials and finishes:

Although steel is a common material for every set of nuts and bolts, having a corrosion-resistant finish proves beneficial if they are exposed to high moisture or pressure-treated lumber. This finishing treatment will prevent the bolts from corrosion and ensure longer durability. Below are some of the standard finishes for different applications:

  • Zinc-plated bolts:

    Well-suited for indoor applications, these bolts have a thin layer of yellow zinc or yellow dichromate coating that prevents corrosion of the bolt. However, they do not provide resistance under high pressure-treated lumber and are unsuitable for exterior use.

  • Hot-dipped galvanized nut bolts:

    They are generally submerged in a series of chemical baths after manufacturing to give them a thick and uniform coating. The thickness of the coating provides high corrosion resistance, thus making these bolts perfect for outdoor use, especially in coastal environments.

  • Stainless steel bolts:

    Because of their high anti-corrosive properties, these bolts are ideal in salt water and chlorine environments. Stainless 316 with high resistance grade is considered the best in such environments.

  • Hardened steel bolts:

    Because of their increased strength, they are significantly used in automotive applications and assemblies. They are made out of steel alloy, mainly comprising copper and zinc.

Types of bolts based on thread types:

Nuts and bolts are broadly classified as coarse-threaded or fine-threaded. In comparison, coarse threads have a higher pitch than fine threaded bolts. Also, fine threads are more prone to damages, fouling, and galling than coarse threads.

However, there are a few advantages of fine threads. For example, they do not easily loosen up, thanks to their smaller pitch. Also, these bolts have higher tensile strength, thus making them perfect for strength-specific applications. Smaller angles further ensure easy tapping of holes into strong materials and thin-walled tubes.

Key factors to keep in mind while buying bolts:

Now that we have seen different types of nut bolts based on various characteristics let us learn about the factors to be considered before buying them.

  • Choosing the right bolt type:

There are plenty of options available in the market when you start looking for bolt types, making the selection more challenging and confusing. Also, some bolts that offer high strength when used in certain materials may not provide similar strength for other materials. Therefore, choosing the right bolt type depending on your application is crucial for smooth installation.

  • Choosing the correct bolt size:

Knowing both the length and the diameter of any bolt is important before using it. The length of a bolt is measured from the flat surface of the head to the tip or end of the screw. The diameter is measured from the outer thread on one side to the outer thread on the other side. Choosing the wrong bolt size can result in misuse of the materials, wastage of time and effort in completing a project or work. So, make sure to have accurate measurements before buying.

  • Choosing the right material:

Remember that a bolt made of stronger material may not necessarily be the right pick for all kinds of applications. For example, hardened steel bolts that offer increased strength are not suitable in saltwater and chlorine environments. Instead, stainless steel with high resistance grades and anti-corrosive properties is preferred for such applications. So, make sure to buy the suitable material that is actually needed for your project or work.


This was a quick guide on different types of nut bolts based on some of the important characteristics. If you wish to purchase these nuts and bolts at reasonable prices and in bulk quantities, we recommend you to browse through the online portal of Moglix, which is India's one of the most trusted online marketplace for all kinds of nuts and bolts.

Bolts: FAQs

Q. What bolt means?

A. Bolts usually have blunt edges and require the addition of a nut and a washer to lock them in place. While the washer helps distribute the load over a larger surface area, the nut holds the bolt in place.

Q. What are bolts used for?

A. They are mainly used to hold together two objects and provide the best holding strength compared to screws and other fasteners.

Q. Which type of bolts is mostly used?

A. Carriage bolts, anchor bolts, flange bolts, and hex bolts are the most commonly used bolt types. From construction to manufacturing and automotive assemblies, these bolts find wide applications.

Q. Where are nuts and bolts used?

A. They are mainly used in fastening machines and structural components made up of either wood, metal, or any other material. Wrenches are mainly required to tighten and loosen nuts and bolts.