Being in existence for many years now, the Metric thread gauges has beaten the test of time as a reference tool used to check the pitch of threads on screws. It has impacted positively to metrology by saving the time wasted in measuring and calculating the angle of threaded material. Profiles of threads can be quickly determined and categorise based on its size and pitch. The metric thread gauge is also referred to as the pitch gauge. It is said to be appropriately used when a type of thread matches a measure because Metric thread gauges will not match and imperial gauge. On the subject matter of thread gauges, the unified national thread gauge, which is symbolized by the UN thread gauge, is also crucial and commonly used. It has subdivided members known as the UNC thread gauge, the UNF thread gauge, and the UNEF thread gauge, with each of them used for specific purposes.
The Metric thread gauge and the UN thread gauge have similar thread forms; hence they tend to have some manufacturing operations. These operations will be discussed below for proper understanding.
Threading: This is an essential operation in the manufacturing of UN thread gauge and metric thread gauge. It involves the production of threads either by ways of cutting, rolling, or grinding, although most threads are by the rolling process. This can be attributed to the benefits of the rolling process that includes reduced fatigue failure and a smooth finish.
Heat treatment: For the production of more durable threads, the hear treatment is usually carried out. It is another vital operation most threads manufacturing companies make use of.
Heading: This is the process of producing threads heads either by forging or by the use of machines. This operation is a crucial one in the production of UN thread gauges and metric thread gauge.
In addition to the primary manufacturing operations of Metric thread gauges and UN thread gauges, this article would also cover up the basic terminologies associated with their use. These terminologies are as follow:
Thread crest: The crest of a thread is an integral part of a thread that can be found in the region of the outer surface for external threads and in the inner diameter for internal threads.
Flanks: These are the straight sides that connect the crest and the root.
Thread root: The root if threads are said to be the groove below the two flanking surfaces of the thread.
Thread pitch: This is expressed in a thread per inch, and it is the distance of the thread that is parallel to its axis.
Pitch diameter: This is the distance between the pitch points in a thread.
Primary diameter: it is also known as the Nominal diameter and happens to be the largest diameter in a thread.
Minor diameter: Also known as the root diameter is the smallest diameter present in a thread gauge.