DIN 931

technical standard that specifies the properties and dimensions of hexagon head bolts with partial thread. It is a German standard, also known as Deutsches Institut für Normung (DIN) 931, and is commonly used in engineering and construction applications.

These bolts are made of carbon steel or alloy steel and have a hexagonal head, which makes them easy to tighten and loosen with a wrench or socket. The partial thread means that only a portion of the bolt is threaded, leaving the rest of the shaft smooth.

The DIN 931 standard specifies the dimensions of the bolt, including the length, diameter, and thread pitch. It also sets requirements for the mechanical properties, such as the tensile strength and hardness, and the surface finish.

Uses of DIN 931

Overall, DIN 931 bolts are widely used in a variety of applications where a strong and reliable fastener is required.

DIN 931 bolts are commonly used in a wide range of applications in various industries, including construction, manufacturing, and automotive. Some of the common uses of DIN 931 bolts are:

1. Structural applications: DIN 931 bolts are often used in construction applications for fastening structural steel members, such as beams, columns, and trusses.
2. Machinery and equipment assembly: They are used in the assembly of heavy machinery and equipment, such as engines, turbines, and generators.
3. Automotive industry: DIN 931 bolts are used in the automotive industry for fastening engine components, chassis parts, and suspension systems.
4. Aerospace: They are also used in the aerospace industry for fastening aircraft components and structures.
5. Marine applications: DIN 931 bolts are commonly used in marine applications for fastening deck hardware, rigging, and other structural components.

Overall, DIN 931 bolts are widely used in applications that require a high-strength and reliable fastener that can withstand heavy loads and stress. They are a popular choice for applications where safety and reliability are critical.

Materials for DIN 931

DIN 931 bolts are available in a variety of materials, and different standards specify the requirements for each material. Here are some of the commonly used materials for DIN 931 bolts, along with the corresponding standards:

Materials specified by ANSI/ASME standards:

• ASTM A193 Grade B7: This material is a high-strength alloy steel used in applications where high tensile strength and resistance to corrosion are required.
• ASTM A320 Grade L7: This material is a low-temperature steel used in applications where the bolt needs to perform in cold environments.

Materials specified by ASTM standards:

• ASTM A307 Grade A: This material is a carbon steel used in general-purpose applications that do not require high strength or resistance to corrosion.
• ASTM A325 Type 1: This material is a high-strength steel used in structural applications.
• ASTM A490 Type 1: This material is a high-strength steel used in heavy construction applications.

Materials specified by DIN standards:

• Steel Grade 8.8: This is a medium carbon steel that has a tensile strength of 800 N/mm² and is commonly used in general-purpose applications.
• Steel Grade 10.9: This is a high-strength steel that has a tensile strength of 1000 N/mm² and is commonly used in automotive and machinery applications.
• Steel Grade 12.9: This is a very high-strength steel that has a tensile strength of 1200 N/mm² and is commonly used in aerospace and other critical applications.

Overall, the choice of material for DIN 931 bolts will depend on the specific requirements of the application, including the load-bearing capacity, environmental conditions, and corrosion resistance.

DIN 931vs DIN 933

DIN 931 and DIN 933 are both technical standards that specify the properties and dimensions of hexagon head bolts, but there are some differences between the two standards:

1. Thread length: The most significant difference between DIN 931 and DIN 933 is the thread length. DIN 931 specifies hexagon head bolts with partial thread, while DIN 933 specifies hexagon head bolts with full thread. This means that the thread on DIN 933 bolts extends along the entire length of the shaft, while the thread on DIN 931 bolts only covers a portion of the shaft.
2. Applications: DIN 933 bolts are generally used in applications where a full thread is required, such as for clamping two unthreaded objects together or where a threaded hole is present. DIN 931 bolts are commonly used in applications where a partial thread is required, such as in structural steel connections, machinery and equipment assembly, and automotive applications.
3. Strength: The mechanical properties of DIN 931 and DIN 933 bolts may differ depending on the material used and the specific requirements of the application. However, in general, DIN 933 bolts may have slightly higher tensile strength compared to DIN 931 bolts due to the full thread design.

In summary, the main difference between DIN 931 and DIN 933 bolts is the thread length, with DIN 931 bolts having a partial thread and DIN 933 bolts having a full thread. The choice of bolt standard will depend on the specific requirements of the application.

DIN 931 vs DIN 960

DIN 960 partially threaded bolts are similar to DIN 931 bolts in that they both have a partial thread along the shank. However, DIN 960 bolts with a partial thread have a finer pitch than DIN 931 bolts and the length of the threaded portion is generally shorter.

The primary difference between DIN 931 and DIN 960 bolts, whether fully or partially threaded, is the thread pitch. DIN 960 bolts have a fine thread pitch, while DIN 931 bolts typically have a coarse thread pitch. This difference in thread pitch can affect the level of precision that can be achieved during installation, as well as the strength and resistance to fatigue of the bolt under certain loading conditions.

Fine Thread Vs Coarse Thread:

The main difference between fine thread and coarse thread is the pitch of the thread, which refers to the distance between adjacent threads.

Coarse threads have a larger pitch, meaning that the distance between adjacent threads is greater than that of a fine thread. This results in fewer threads per unit length of the bolt, making coarse threads faster to install and easier to tighten with a higher torque than a fine thread of the same size. Coarse threads are commonly used in applications where high clamping force is required, such as in automotive and construction industries.

On the other hand, fine threads have a smaller pitch, meaning that the distance between adjacent threads is smaller than that of a coarse thread. This results in more threads per unit length of the bolt, which increases the thread engagement and can provide a more precise and uniform clamping force. Fine threads are commonly used in applications where high tensile strength and resistance to fatigue are required, such as in aerospace and military industries.

In general, the choice between fine thread and coarse thread depends on the specific application and the requirements for the bolt. Factors such as the type of material being fastened, the expected loads and stresses, and the need for precise torque control or fast installation can all influence the choice between fine and coarse threads.