The thread pitch is its fundamental characteristic. To determine its value, you can use a regular ruler. To make the measurement more accurate, it is better to use special devices.
It is necessary
- - threads;
- - ruler;
- - thread gauge.
The pitch of the thread is the distance between the sides of the same name of the thread profile. It is he who needs to be measured in order to correctly determine this characteristic. Do it roughly with a regular ruler. Measure the length of the specified number of threads.
Keep in mind that the more turns are measured, the smaller the error will be. Therefore, depending on the size of the thread for measurement, count from 10 to 20 turns. Divide the length of the counted number of turns, measured with a ruler, by the number of these same turns. This will be the thread pitch. It is better to measure the length in millimeters. In the event that the thread pitch is to be measured in inches, convert the value.
For example, if you need to measure the pitch of a certain thread, count 20 turns to reduce the measurement error (if there is this number of turns, if not, take less). Suppose, when measuring, you get a thread length of 127 mm. Divide this number by 20 turns, and you get 6.35 mm. This is the thread pitch in millimeters.
If there is a need to convert it to inches, take the value of one inch in millimeters, which is 25.4, and divide the resulting step 6, 35 by this value. In this case, the result is 0, 25, or 1/4 "(inch). If the value is not as accurate, round it to the nearest fraction of an inch.
Since the vast majority of threads are made to approved standards, in order to unify this connection, measure the thread pitch with a thread gauge. This device is a set of special steel plates that have cutouts corresponding to different types of threads. The plate is marked with values corresponding to a particular step length in millimeters or fractions of an inch. Measure by placing different plates on the thread parallel to the thread axis and check the gap between the teeth with light. If it disappears, the value on the insert is the one that indicates the pitch of the thread to be measured.