screw thread A screw thread is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a ''straight'' thread and t ...

, often shortened to ''thread'', is a helical structure used to convert between rotational and linear movement or force. A screw thread is an inclined plane wrapped around a

cylinder A cylinder () has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base. A cylinder may also be defined as an infinite ...

cone In geometry, a cone is a three-dimensional figure that tapers smoothly from a flat base (typically a circle) to a point not contained in the base, called the '' apex'' or '' vertex''. A cone is formed by a set of line segments, half-lines ...

in the form of a helix, with the former being called a ''straight'' thread and the latter called a ''tapered'' thread. More screw threads are produced each year than any other

machine element Machine element or hardware refers to an elementary component of a machine. These elements consist of three basic types: # ''Structural element, structural components'' such as frame members, Bearing (mechanical), bearings, axles, Spline (mechan ...

.. Threads are generally produced according to one of the many standards of thread systems. Standards Development Organizations such as the

American National Standards Institute The American National Standards Institute (ANSI ) is a private nonprofit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organiz ...

American Society of Mechanical Engineers The American Society of Mechanical Engineers (ASME) is an American professional association that, in its own words, "promotes the art, science, and practice of multidisciplinary engineering and allied sciences around the globe" via "continuing edu ...

SAE International SAE International is a global professional association and standards organization based in Warrendale, Pennsylvania, United States. Formerly the Society of Automotive Engineers, the organization adopted its current name in 2006 to reflect bot ...

International Organization for Standardization The International Organization for Standardization (ISO ; ; ) is an independent, non-governmental, international standard development organization composed of representatives from the national standards organizations of member countries. M ...

Deutsches Institut für Normung ' (DIN; in English language, English, the German Institute for Standardisation) is a Germany, German non-profit organization and acting as national organization for standardization. DIN is the German International Organization for Standardizat ...

(German Institute for Standardization), British Association and others produce these standards for manufacturers to follow when producing threaded components.

Currently used thread standards

Obsolete thread standards

See also

Notes

References