April 24, 2019

How to Solve the Undersirable Effects of the Silver Contact Riveting Parts

Heju stamping worked out silver contact riveting parts in die technology in 2013. The riveting parts effect as contact and breakover for relay products. It is widely used in medical, communication, transportation, electricity, electronic and other fields. During stamping production, we must do concrete analysis for the undersirable effects, and then take effectural measures to sovle the problem fundamentally. Only in this way, we can run smooth production and cut down the production cost. Now we’ll introduce the situations we met during our production, also shows the handing mathod for tooling maintain engineer reference only.

The undersirable effects of the silver contact riveting terminal

  1. Contact material overflow : the second step cavity is a bit small.
  2. Riveting gap: Die plate and stripper didn’t run over at the second stage of riveting.
  3. Contact notch:the pre-rivet contact thickness is a little thin at the first stage, it caused the bottom of die cavity can not touch the contact at the second stage.
  4. Contact deformation: As the bottom hole punched a bit bigger (2.02mm) at the second stage(the first stage is 1.63mm) deformation caused by too much material expansion.
  5. Contact fall out: The pre-rivet stage punched not enough; the shim on the stripper plate is easy to be loose.
  6. Contact filamentous bruised:As the concentricity of the two riveting stage isn’t exactly the same, after pre-rivet, contact diameter is a little big, caused clout at the die cavity edge.
  7. Sector crashed of the contact: The rivet is in the tieing of the vibrating plate and the tieing between vibrating plate and die. Crashed by dislocation and big amplitude of the vibrating plate’s tube.
  8. Contact’s surface is too rough:There is foreign matter or oil in die cavity when change material. The air pressure have water in it.
  9. The speed of the riveting contact entering into the tooling is too slow: Air pressure is too big in the tooling, when push forward, the rivet maybe blocked by the air.
  10. The riveting contact droped down in the vibrating plate: When vibrating plate works for a long time, rivetings may be blocked by some mess in the corner of the orbit.

Improvement measures

  1. Make the die cavity with this specification: diameter: 2.77mm; deepth:0.48mm; total height:25.02mm.
  2. Add the height of die plate or stripper insert of the second stage riveting.
  3. Under the condition of rivet do not fall off, you can do in this way: first cut down the punch height of first riveting stage, second add the die plate insert height of the second stage riveting, third, change big diameter rivet into small ones.
  4. Cut the punch height of the second riveting stage, make the unbroken size in the range of 1.90-1.95mm, height is about 1.99mm.
  5. Add first stage riveting punch’s height; Guide plate turning groove deepth 0.87mm.
  6. Under no falling for the rivet,cut down the height of fist stage riveting punch or change small rivet contacts.
  7. Make the vibrating plate’s four corner stable,no waggling,no gaps for the two layups.
  8. Clean the die cavity when change material. Close air pressure when stop the machine.
  9. Turn down the air pressure and make sure rivetings can be pushed in die.
  10. Each shift need to clean the stainless steel zone of the vibrating plate via non-dust cloth, the rest can be cleaned via dry cloth.