we are using fine blanking progressive tools.... it happens flatness problem often...in progressive tool.... how is it happening... and give me some solution for correct this.
I haven't worked with fine blanking dies, but in standard progressive dies where blank flatness is an issue (which is common), I usually blank " under pressure". That is I use a heavily spring loaded pressure pad in the female die cavity to support the blank and push it back up into the strip. the blank is then knocked out of the strip in the next die station by a punch with significantly greater clearance than the blanking punch.
The trick is that the first blanking punch should not penetrate the stock more than 2/3 to 3/4 of its thickness. Just enough to develop the fracture. In a fine blanking situation where the shear is generated to the full stock thickness, I am not really sure how this will work. I think that the punch will have to penetrate to almost the full stock thickness, and a lot of stripper pressure will be required to keep the strip flat when the blank is pushed back in. But then, it is my understanding that very high stripper pressure is required in the fine blanking process.
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Flatness Problem In Fine Blanking
Re: flatness problem in fine blanking
