Nut Bolt Weight Chart in KG – Nut Bolt & Washer Weight Guide

Engineers, procurement teams, and fabricators can benefit from a nut bolt weight chart in kg as it will enable them to calculate fastener weight in seconds without needing to weigh every piece. Being aware of the weight of each bolt, nut, or washer makes it easy to create a bill of materials, estimate freight costs, or match a nut bolt weight table in kg to that stated in a draft or drawing specification thereby avoiding costly blunders. 

Unifit Metalloys, a producer of standard steel, stainless steel, alloy steel, and duplex fasteners has compiled this nut, bolt, and washer weight guide that covers all sizes ranging from M6 to M64. In an actual project, it's easy to miss a number in your fastener weight estimate, particularly on a large project with thousands of bolts. This is where a precise nut bolt weight chart will come in handy. 

What Is a Fastener Weight Chart?

A reference table that gives the approximate weight (in kilograms) of each nut bolt and washer size, length and material is called a nut bolt weight chart. It can be used by engineers and buyers to quickly determine the total weight of a fastener assembly without having to weigh each part. These charts are particularly helpful in industries that require ordering fasteners in larger quantities, such as oil & gas, power generation, construction and pipeline projects. A weight chart provides a quick reference for a standard weight, eliminating the need to manually weigh thousands of pieces. 

Weight can vary depending on:

• The diameter and length of the fastener.
• The type of thread, full thread or half thread.
• Mechanical properties, such as strength, hardness, or ductility, Mild steel or carbon steel, or stainless or alloy steel
• Standard was followed, IS, DIN, ISO or ASME 

How to Calculate Bolt, Nut & Washer Weight?

A simple engineering formula is used to calculate the weight of any fastener, considering its volume and its density. 

Weight = Volume × Density

For a bolt weight formula, the volume is calculated as:

Volume = π/4 × d² × l

Where:

• d = diameter of the bolt (in cm)
• l = length of the bolt (in cm)
• π = 3.14

Worked Example: For an M16 bolt (16 mm diameter) with a length of 100 mm, using mild steel density of 7.85 g/cm³:

Volume = π/4 × (1.6)² × 10 = 20.11 cm³ Weight = 20.11 × 7.85 = 157.9 grams ≈ 0.158 kg

The same approach is used for nuts and washers, but the shape has to be considered – in the case of nuts a hexagonal prism with a hole, and in the case of washers a flat ring (outside diameter – inside diameter) x thickness.

The weight is strongly influenced by the density of the material. Here are some quick references: 

Nut Bolt Weight Chart in KG (M6 to M64)

If you need to know how many kgs a nut bolt has, please use this chart.

The following is a typical nut bolt weight chart for commonly used sizes. Approximate weights are based on the assumption of full thread hex bolts with mild/carbon steel.

Note: The values may differ slightly with each type of bolt, length, manufacturing standard (IS, DIN, ISO or ASME).

Washer Weight Chart in KG

Although washers are an important component of most fastener assemblies, they are frequently omitted from weight charts. The following is a quick reference of typical flat washer weights. 

Spring washers are lighter than flat washers for the same size, generally about 30-40%, because the coiled profile means that they typically are more open. When determining total assembly weight, always verify the type of washer, flat washer, square washer or spring washer.

Stud Bolt with Hex Nut Weight Chart

Stud bolts are a type of fastener that is often used in flange connections with two hex nuts, increasing the load on the fastener combination. Here follows a reference, for some typical lengths of 100 mm. 

Weight Chart by Material

The weight of fasteners is highly dependent on the density of the material they are made from, so the weight of a given fastener size will vary depending on the material. The following comparison is for an M20 x 100 mm bolt. 

Fasteners are produced in a variety of materials (Stainless Steel, Carbon Steel, Alloy Steel, Duplex, Super Duplex, Monel, Inconel, Hastelloy etc) at Unifit Metalloys, enabling you to precisely calculate the weight of the fastener for your exact grade requirement. 

Factors Affecting Nut, Bolt & Washer Weight

• Material and Grade
  Heavier alloys and other nonstandard materials, such as Inconel or Hastelloy are typically a bit heavier than basic carbon steel, adding just a little weight.

• Coating
  Galvanised, zinc-plated or PTFE-coated fasteners will be slightly heavier than uncoated fasteners because of the coating layer.

• Thread Type
  Full-thread bolts are lighter than half-thread bolts of the same length because they have a larger amount of material taken from the top of the shank to cut the threads.

• Custom Sizes
  Custom orders (e.g., non-standard length or custom head design) may add or remove weight from standard charts, and should always be checked with the manufacturer. 

Why Accurate Weight Charts Matter

• Procurement & Costing
  Fasteners tend to be sold by the pound, particularly when ordered in large quantities. A precise chart guarantees fair costing as well as staying clear of over-payment and inadequate budgeting.

• Freight & Logistics
  Shipping weight directly influences freight cost, especially when it is for export orders. It's helpful to know exactly how much it will weigh in advance, so as to avoid any unpleasant surprises at the end when it comes time to pay.

• Project Planning
  In EPC/construction projects, thousands of fasteners will be applied in piping and structure systems. Correct weight estimation helps in proper material planning and inventory management. 

Why Choose Unifit Metalloys?

As a trusted industrial fastener supplier and manufacturer of nut bolt weight charts in Mumbai, Unifit Metalloys offers you top-quality nut bolt solutions. What are the unique qualities they have?

• Manufacturing for a variety of Stainless Steel, Carbon Steel, Alloy Steel, Duplex and exotic alloys.
• Fasteners manufactured based on IS, DIN, ISO and ASME standards.
• Manufacturing processes that meet the requirements of ISO 9001:2015. Manufacturing processes that are certified as meeting ISO 9001:2015.
• Consistent and accurate precision-engineered bolts, nuts and washers.
• A presence in oil & gas, power generation and infrastructure industries.

They strive for quality so that all fasteners that they deliver are as per the specification, size and weight stated on the paper. 

Final Thoughts

A nut bolt weight chart can seem like a straightforward reference table, however it is very much a vital component of procurement, costing and project preparation. Whether it's bolts and nuts or the sometimes-forgotten washers, accurate weight is crucial to prevent costly time and money mistakes on any industrial project.

From mild steel fasteners for normal applications to stainless steel and alloy fasteners for critical, high pressure applications, a good manufacturer such as Unifit Metalloys will ensure that the fasteners are delivered on time and of the correct weight and quality. 

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