T10A thread ring gauge adopts medium frequency induction heating machine for heat treatment, the effect is good.

The T10A threaded ring gauge was originally heated in a salt bath and quenched in two liquids. After quenching, the inner diameter was reduced by 0.30-0.35mm, and the roundness error was 0.06-0.08mm. After finishing, the yield rate was low and there were many reworked products. Nowadays, a medium frequency induction heating machine is used for heat treatment, which has good results and meets its working requirements.

The medium frequency induction heating machine heats the T10A threaded ring gauge by heating the ring gauge to the austenite temperature and maintaining it for a certain period of time, then quenching and cooling it to close to the Ms point, and then inserting the prepared limited-shaped plunger into the inner diameter to continue cooling. The ring gauge is allowed to transform from austenite to martensite in a shape-limited state. During the phase change process, since the outer diameter of the plunger is exactly equal to the inner diameter of the ring gauge thread, when the inner diameter of the thread contacts the limited-shaped plunger, its volume change and redistribution can be reasonably controlled, and under very small contact stress Under the action of the ring gauge, the ring gauge can easily adapt to the requirements of shape restriction and achieve the purpose of micro deformation.

According to the size of the effective thickness of the thread ring gauge, the following two restrictive quenching methods can be adopted.

1) Effective thickness>25mm. The medium frequency induction heating temperature is 800°C. After heat preservation, it is quenched into 5% (mass fraction) NaOH aqueous solution. When it is cooled to close to Ms, it is quickly loaded into the shape-limiting plunger, and then immediately filled with oil to continue cooling. Finally, together with the shape-limiting plunger Temper together and withdraw the plunger after tempering. The inner diameter shrinkage was measured to be 0.04mm, the roundness error was <0.03mm, and the hardness met the design requirements, providing favorable conditions for the next precision grinding process.

2) Effective thickness <25mm. Use a medium frequency induction heating machine for heating. The heating temperature is 820°C. After being kept warm for a certain period of time, it is quenched in an alkali bath at 190°C for 15-20 seconds. Quickly lift up and wipe off the alkali solution, install the plunger, add oil to cool, and then clean. Temper at low temperature. After heat treatment, the inner diameter shrinkage is ≤0.040mm, and the roundness deformation is <0.015mm.

The T10A thread ring gauge uses a medium frequency induction heating machine for heat treatment. Compared with other heat treatments, it has great advantages and greatly reduces the error rate of the workpiece. This article briefly introduces two form-limiting quenching methods. After many manufacturers adopt the above methods, the T10A thread ring gauges produced are of good quality and meet their working requirements.