ISO metric thread

What is the ISO Metric Standard Thread?

The ISO metric standard thread is an internationally standardized thread system widely used in machining, machine shops, and manufacturing facilities. It is based on the metric system and defined by the ISO 68-1 standard. This type of thread is the most commonly used, especially for bolts, nuts, and other fastening elements, because its standardization ensures compatibility between components from different manufacturers.

Characteristics of the ISO Metric Standard Thread

ISO metric threads have a triangular shape and feature a 60° flank angle. The nominal size of the thread is given in millimeters; for example, M10 refers to a 10 mm nominal diameter. These threads are available in both coarse and fine variants, with fine threads having a smaller pitch than coarse ones, which improves clamping force and helps prevent loosening due to vibration.

Use of ISO Metric Standard Threads in Machining

In machine shops, the ISO metric standard thread is the primary choice for various fastening solutions. Coarse threads are commonly used in structural applications and general machining due to their higher strength and better durability. Fine threads are especially suited for applications that require more precise adjustment or higher tensile strength, such as in the aerospace and automotive industries.

Manufacturing ISO Metric Standard Threads

In machining, ISO metric standard threads can be manufactured using various methods, such as thread turning, milling, or rolling. Thread accuracy is specified using standard tolerance classes, such as 6g for external threads and 6H for internal threads, ensuring reliable fit between parts.

Summary

The ISO metric standard thread is a globally standardized metric thread form widely used in machining and the manufacturing industry. Its precisely defined properties—such as the 60° angle and various pitch options—ensure reliable and consistent fastening in different applications. This thread type is an essential part of modern manufacturing, guaranteeing the global compatibility of components.