All Categories

Home> Blogs> Influence of pin floating on repeatability of gauge

Influence of pin floating on repeatability of gauge

2021-07-19 Page view : 159 views

When the part is placed on the inspection tool, because there will be a gap between the locating pin and the reference hole of the part, the hole pin floating will occur. How much impact will the hole pin floating have on the measurement of the part?

case analysis

We will take the following assembly as an example. The figure shows RPS points. We will model the features of the fixture and parts, and then select Y-direction measuring points for analysis.

Wechat pictures_ twenty trillion and two hundred billion four hundred and fifteen million one hundred and sixty-four thousand two hundred and thirty-one

Modeling analysis

In VSA, the modeling settings are as follows. Monte Carlo algorithm will be used to simulate 5000 times of assembly, in which the diameter of the reference hole is 25.4 ± 0.1mm. The influence of the pin floating on the measuring point when the pin positioning diameter is 25.35mm, 25.3mm and 25.25mm will be evaluated respectively. At this time, the limit distribution is selected for pin assembly.

Wechat pictures_ twenty trillion and two hundred billion four hundred and fifteen million one hundred and sixty-four thousand three hundred and fifteen
OEM custom aluminum CNC milling parts
simulation result

There will be deviation at the measuring point due to the hole pin floating. By comparison, our company adopts 25.35mm in the value of the gauge pin. The diameter of the pin varies slightly from company to company, but the final criteria are repeatability and reproducibility.

Wechat pictures_ twenty trillion and two hundred billion four hundred and fifteen million one hundred and sixty-four thousand three hundred and fifty-nine

Of course, in order to reduce the hole pin floating, tapered pin or spring pin can be used to make the parts measured in RFs state. If the part is measured in MMB state, it is necessary to evaluate whether the drawing is reasonable or not. Otherwise, it may not pass the test when making the repeatability and reproducibility of the fixture.

发表评论

您的电子邮箱地址不会被公开。 必填项已用*标注