A brief discussion on Thread Gage Calibration

A thread gage device is used to examine the threaded part’s acceptance. The main role of a thread gauge is to check the external or internal threaded part. There is a specific procedure of thread gage calibration to carry on. This is mainly used to check X-tolerance thread ring gages in a calibration lab where the temperature is controlled purposely for the best result.

Various types of thread gage are available such as API to spec Q1, API 5B plug and API 7–2 plug etc. They are mainly used to observe the strength, durability, and tolerance etc to ensure the best of the quality of a material.

The whole procedure of Thread Gage Calibration is mentioned below for the better understanding of the need of it. This is comprised of some simple steps as follows-

· Firstly, choose the set of a master set plug that goes with the ring gages. To confirm the settings of the master set plug, it is mandatory to know the class size and pitch diameters as per ring gages. The set plug has to be clean and sturdy.

· Then, lubricate the set of the master plug with a thin film or viscosity oil to minimize the friction

· If there are any impurities found in the ring gages, this must be cleaned properly.

· After that, remove the existing sealing wax using a knife carefully so that no part is broken

· Loosen the ring gage locking screw by turning it anti-clockwise very carefully

· Turn the adjusting screw clockwise. It will help to open the ring to a larger pitch diameter than the setting plug.

· Turn the ring gage onto the setting plug to the back. Turning the ring gage onto the setting plug henceforth helps to extend one thread approximately above the last thread present on the setting plug. This helps to promote more uniform and even wear over the whole thread length of the setting plug.

· Move the adjusting screw anti-clockwise and turn the ring on the setting plug all over until and unless there is a slight gap that appears between the two gages

· Press the ring with a small hammer to ensure that the ring has been properly seated and fixed, and then recheck to reassure that the whole process has been done carefully.

· Now separate the set plug from the ring

· Now the gage is ready for service