What Does DIN Mean for Bolts?
DIN stands for Deutsches Institut für Normung, the German Institute for Standardization. The DIN system provides standardized specifications for bolts, screws, nuts, washers, and other fasteners. A DIN number is a unique identifier that ensures a specific fastener conforms to the internationally recognized standards set by this institute. For example, a DIN 933 hex bolt follows a specific design and quality standard to ensure its compatibility across various applications globally.
The DIN system helps engineers, manufacturers, and construction professionals know exactly what to expect from a fastener, ensuring consistent quality, durability, and compatibility.
What Is the Difference Between DIN 912 and DIN 7991?
Both DIN 912 and DIN 7991 refer to hexagon socket head cap screws, but they have different specifications regarding the head design and application.
DIN 912
Shape: This is a hexagon socket head cap screw with a cylindrical head. The screw has a smooth, flat top and a recessed socket for driving the screw with a tool.
Application: These bolts are commonly used in machinery and equipment where a high level of precision and aesthetic appearance is required. The recessed socket allows for installation in spaces with limited clearance.
DIN 7991
Shape: Also a hexagon socket head cap screw, but the head design is slightly different, often having a more rounded top than the DIN 912.
Application: Similar to the DIN 912, but the differences in head design make it more suited for certain aesthetic or functional purposes, especially in tight spaces or where the flush design is needed. DIN 7991 bolts are typically used in industrial applications and machinery where performance and clearance are critical.
In essence, the primary difference is the head design, with DIN 7991 offering a more flush-fitting head compared to DIN 912.
What Is a DIN 933 Bolt?
A DIN 933 bolt is a fully threaded hexagon bolt. These bolts have threads running along the entire length, making them versatile and suitable for a variety of applications. DIN 933 bolts are commonly used in applications where high precision is essential, such as in automotive or construction projects.
Key Features
Fully threaded: Ensures a secure and strong grip when inserted into nuts or tapped holes.
Hexagonal head: Provides a larger surface area for tightening with a wrench.
Materials: Available in a variety of materials, including steel, stainless steel, and others, to suit different environmental conditions.
DIN 933 bolts are essential in heavy-duty and high-stress applications where secure fastening is critical.
What Is the DIN Number on a Screw?
The DIN number on a screw indicates the specific standard that the screw follows. Each type of screw has its own DIN number, which ensures that it is manufactured to a particular set of standards for dimensions, thread pitch, material composition, and other technical specifications.
For example:
DIN 933 is for hex bolts, as mentioned earlier.
DIN 7985 is a standard for pan head screws.
DIN 964 covers slotted pan head screws.
Each of these numbers corresponds to specific characteristics of the screws, such as their shape, material, and application. By referencing the DIN number, engineers and buyers can easily identify the appropriate screw for a particular use.
Conclusion
DIN numbers are an essential part of the fastener industry, providing standardized references that ensure compatibility, quality, and performance in various applications. Whether you're working with DIN 912, DIN 7991, or DIN 933, understanding these standards helps ensure you select the right fastener for the job. DIN 912 and DIN 7991 bolts, though similar, differ in head design, with DIN 7991 providing a flush-fit for specific applications. DIN 933 bolts, being fully threaded, offer strength and versatility in various industries. Additionally, the DIN number on screws is crucial for identifying the correct fastener for your needs, ensuring precision and reliability in any project.
