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40 ORÇUN ASLAN

 Visual defects can be only visual and not harmful, but also they can effect roughness
    and again performance/abrasion

 If hardness values won’t match, it can cause malfunction of engine due to wrong timing
    of a valve with worn tip-end

 Wrong structure of material also may lead to failure of the valve and also failure of
    engine

 If welding stress relief is not suitable, it will cause welding to crack and eventually
    break

5. FMEA Sheet

Since the FMEA sheet for this manufacturing process is very long, because it contains way
more risks, a little part for the FMEA sheet will be shared in this article as a screen, to give you
an idea what it looks like to make one for this process.

POTENTIAL POTENTIAL                 CURRENT CONTROLS                                                       S O D R RECOMME
                                            (Prevention)
EFFECT(S) OF CAUSE(S) OF                                             CURRENT CONTROLS (Detection) E C E P NDED
                                                                                                                  V C T N ACTIONS
FAILURE                  FAILURE

Possibility of a Incorrect set up Visual Control 5pcs set up         Visual Control 5pcs 2 hours           8 2 4 64 N/R

premature engine                    Crack Control 100pcs set up      Crack Control 100pcs day

failure due to                                                       Crack Control 100% Final
                                                                     Visual Control 5pcs 2 hours
valve head cracks Incorrrect blade Visual Control 5pcs set up                                              8 2 4 64 N/R

                                    Crack Control 100pcs set up Crack Control 100pcs day

                                                                     Crack Control 100%       Final
                                                                                              Inspection
Reduction of             Incorrect set up Dimensional  5pcs  set up  Dimensional  5pcs        2 hours      5 2 5 50  N/R
                                                       5pcs  set up               5pcs                     7 2 5 70  N/R
production rate                             Control                  Control                  2 hours
Scrapped valve           Incorrect set up Dimensional                Dimensional

due to length                               Control                  Control

undersized.

Possibility of           Incorrect  Upsetting 100% poke- Upsetting 100%                       poke-yoke    8 2 3 48  N/R
engine failure due                                                                            every shift
to cracks,head           upsetting speed- temp. check        yoke temp. check

                         temperature bUypps.yTroemmepter 1pcs unit bUypps.yTroemmepter 1pcs

                                    Check by                 setup Check by hand

                                    Fighuanrde 6. Screen sample from tphyeroFmMetEerA sheet.

Acknowledgement

I would like to express my special thanks of gratitude to my teacher (Prof. Dr. Hakan Akyıldız)
as well as our company (Supsan – Borusan Holding) who gave me the opportunity and
knowledge to do this studies.

References

      [1] "History of Technology: Internal Combustion engines". Encyclopedia Britannica.
            Britannica.com. Retrieved 2012-03-20.

GiDB|DERGi Sayı 5, 2016
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