METODOLOGI SIX SIGMA
PERTEMUAN 10
(Six Sigma Sebagai Sistem Pengukuran)
OLEH: EMELIA SARI
Fokus Six Sigma

Pengurangan Cycle Time
 Pengurangan Jumlah Produk Cacat
 Kepuasan Pelanggan
2 Arti Penting Six Sigma

Six Sigma sebagai filosofi manajemen
 Six Sigma sebagai sistem pengukuran
Six Sigma Sebagai
Filosofi Manajemen

Six Sigma merupakan kegiatan yang
dilakukan oleh semua anggota perusahaan
yang menjadi budaya, dan sesuai dengan
visi dan misi perusahaan, dengan tujuan
meningkatkan efisiensi proses bisnis dan
memuaskan pelanggan sehingga
meningkatkan nilai perusahaan.
Six Sigma Sebagai
Sistem Pengukuran

Six Sigma diterapkan untuk memperkecil
variasi.
 Six Sigma sebagai satuan pengukuran
menggunakan Defect per Million Opportunities
(DPMO) sebagai satuan pengukuran.
 PPM pada umumnya menggambarkan jumlah
yang tidak memenuhi syarat (defective).
 Suatu bagian yang tidak memenuhi syarat
(defective) mungkin mengandung beberapa
cacat (defects)
Six Sigma Sebagai
Sistem Pengukuran (2)

DPMO merupakan ukuran yang baik bagi
kualitas produk ataupun proses sebab berkorelasi
langsung dengan cacat, biaya dan waktu yang
terbuang.
 Selain DPMO, six sigma juga menggunakan
satuan pengukuran berupa persentase
keberhasilan (yield percent).
 Yield percent: persentase produk yang bebas
defect.
Cara Menghitung DPMO

Hitung Defect per Unit (DPU), dimana:
DPU = Total Kerusakan : Total Produksi

Hitung DPMO dengan terlebih dahulu
menentukan probabilitas jumlah kerusakan
DPMO = (DPU x 1 juta) : Probabilitas kerusakan
Cost of Poor Quality

One of the differences between a Six Sigma
quality improvement approach and many
prior quality programs is the emphasis on
financial returns.
 Because Six Sigma is a business initiative
rather than a quality initiative it makes
sense that financial returns of Six Sigma
projects are measured
COQ and COPQ

The cost of quality (COQ) refers to the
costs associated with preventing defects.
 The cost of poor quality (COPQ) refers to
the costs associated with failure in the
process.
 We will examine preventive and detection
costs in terms of COQ and failure costs as
COPQ.
Preventive Cost of Quality

Preventive costs are the costs of doing it right
the first time.
 They are the least costly of the three categories
because costly mistakes are prevented from
happening in the first place.
 Preventive costs prevent failures, thus ensuring
that customer requirements are continually met.
 Preventive costs are also referred to as the cost
of conformance in manufacturing and the cost of
compliance in transactional services.
Preventive Cost of Quality (2)











Design for Six Sigma
Process improvement
Hiring
Education
Training
Quality reward and recognition programs
Planning
Supplier certification
Customer surveys
Statistical process control
Preventive maintenance
Appraisal Cost of Quallity

Appraisal costs, also called detection costs, are
the costs to find things that were not done right
the first time
 Appraisal costs, like preventive costs, are
grouped under the cost of compliance; they are
the costs of activities needed to evaluate
compliance to customer requirements.
 Appraisal costs, although higher than preventive
costs, are less than the cost of failure, because
appraisal activities prevent the process from
producing defective products or services.
Appraisal Cost of Quallity (2)

Inspections
 Authorizations
 Audits
 Proofreading
 Customer surveys
 Statistical process control
 Spell checking
 Call monitoring
Failure Cost of Quality

Also known as the costs of noncompliance,
failure costs are the costs of not doing
things right the first time.
 There are two categories of failure costs:
internal failure and external failure.
Internal Failure Cost

Internal failure costs include the cost of
fixing mistakes, better known as rework.
 These are failures that are found and fixed
before getting to the customer and the costs
associated with that.
 Internal failure costs are usually associated
with the “re-” words, such as rectification,
rework, reinspection, review, and rewrite
Internal Failure Cost (2)

Scrap (wasted paper, machines, toll
charges)
 Excess labor
 Overtime
 Staff absenteeism, turnover, and health
costs
External Failure Cost

External failures are the worst of all the
quality costs.
 These are the failures that are detected by
customers and the costs of activities
associated with meeting customer
requirements after delivery of the product or
service to the customer
External Failure Cost (2)

All of the costs of internal failures
 Warranty costs
 Labor costs to investigate
 Regulatory investigative costs
 Lawsuits
 Lost business
 Product recalls
 Service failur
Cost of Quality Profiles

In the typical service company, COQ
accounts for 30 to 50% of revenues.
 It is slightly lower in manufacturing
companies — 15 to 35% of revenues
Cost of Quality (COQ)
in Year 1 (before Six Sigma)
Cost of Quality (COQ)
5 years into Six Sigma.
Cost of Poor Quality

COPQ satuan pengukuran yang juga
digunakan dalam metode six sigma
 COPQ : biaya-biaya atau kerugian yang
dikeluarkan, yang diasosiasikan dengan
penetapan kualitas produk atau jasa yang
tidak bagus (cacat/ defect)
 COPQ melibatkan biaya-biaya yang
mengisi gap antara biaya/ kerugian kualitas
produk yang diinginkan dengan biaya/
kerugian kualitas produk/ jasa aktual
Cost of Poor Quality (2)

Biaya/ kerugian ini termasuk juga biaya/
kerugian yang dialami karena loss
opportunity sampai hilangnya sumber daya
dalam kegunaannya memperbaiki produk/
jasa yang cacat (defect)
 COPQ tidak melibatkan biaya pendeteksian
ataupun biaya pencegahan terhadap
terjadinya produk/jasa yang cacat/ defect
Penghitungan COPQ

Potensial loss yang dialami =
(Kapasitas produksi x Persentase defect) x value @ produk

Potensial benefit =
Loss actual – Loss setelah perbaikan
Terima Kasih