No go tip enter into the product

[PARAMESWARAN]

We are doing stamping operation. In 2 mm thickness plate we are stamping 6.21+0.03 mm bore. Plug gauuge is being used for checking. NOGO gauge size is 6.239/6.241. Tip of the no go gauge is entering into the bore and not completely. Whether any standards is there to take decisions on the plug gauge measuring. And shall we accept the component if nogo tip enter into the bore. please help anybody.

[Kelly_Bramble]

LMC = diameter 6.24, therefore the no-go guage your'e using is correct (6.239/6.241).

The absolute size limits of the hole feature is diameter 6.24, so the gauge is telling you the hole is either line to line + or some size less than LMC. Based on the size of no-go guage you are using further investigation is required.

If you know what the mating size of the mating part and installation is going to be by statistical analysis, measured data or worst case analysis and that shows the installation is free and clear - accept it. Otherwise reject, rework or whatever is required. The good news is that you can remove material to to save the part.

[PARAMESWARAN]

Thank you very much for the reply. As said earlier we are having mechanical press and doing conventional stamping operation with progressive die tooling. While doing piercing operation, component will have straight land & secondary shear around 30 %. No go gauge is answering in the secondary shear side up to 30 - 40 %. Since sheet thickness is only 2 mm, decision is being taken on eye sight measuring. whether any fool proof measuring method is available for this type of hole inspection and measuring instrument wants to suit for mass inspection method at shop floor.