. . 2556 16-18 2556

:

Productivity Improvement by Defect Reduction in Fuel Hose

Case Study:Automotive Part Manufacturer

1 2*

1,2

E-mail: umapornpd@gmail.com1 E-mail: natanaree.s@fitm.kmutnb.ac.th2*

Umaporn Pogdang1 Natanaree Sooksaksun2*

1,2Department of Industrial Management, Faculty of Industrial Technology and Management

King Mongkut�s University of Technology North Bangkok Prachinburi

E-mail: umapornpd@gmail.com1 E-mail: natanaree.s@fitm.kmutnb.ac.th2*

1) 2)

3) 4)

2.55 2 Cap

4

1.66 65,127.6 781,531.2

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Abstract

The objectives of this research are to study the defect in a process of fuel hose, to analyze the cause and propose the guideline and to use the guideline to solve problems. The methodology of this research

has 5 steps. 1) To study the process of fuel hose. 2) To define the defect in a process of fuel hose and select the significant defect by using pareto principle. 3) To analyze the cause of the significant defect by

using cause and effect diagram and to propose the guideline for reduce the defect. 4) To implement the

guideline and compare the result. From the data collection, the process of fuel hose are extrusion, cutting, pre-curing stock, put in shape, curing, take off mandrel, clean, inline inspection, assemble; after

that, final inspection before packing. From the data collection, the defects in the process equal to 2.55% that is over 2% the limit of company. From the pareto principle, there are 4 significant defect type. 1) The

fuel hose was wrinkled. 2) The cap on the end of a hose. 3) The rubber mouth ulcers. 4) The skin of fuel hose has holes. There are the main causes of four defect types. Employees do not follow the

procedures. The process of put the work piece in shape is wrong. Some machine is the damaged and dirty. Raw rubber is not the standard. The guidelines for solving are training staff, set working standard

and improvement machinery was damaged by cleansing as plan. Moreover, try out the rubber to the

appropriate value. When the guidelines are used, the percentage of defect is decreasing from 2.55% to 1.66% and the cost reduces by approximately 65,127.6 bath per month or 781,531.2 bath per year.

Keywords: Defect, Fuel Hose, QC tools

1.

. .2555

1

1 (Fuel Hose)

2.55

1

( ) ( )

%

Oil cooler hose 43,974 683 1.55

Air condition hose 32,481 532 1.64

Fuel inlet hose 33,252 569 1.71

Water hose 34,394 654 1.90

Water by pass

cover

38,389 814 2.12

Vacuum hose 34,067 759 2.23

Power steering 32,062 715 2.23

Fuel hose 33,849 864 2.55

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2.

2.1

(Kaizen) ( Continual

Improvement) (KAI)

(Change) (ZEN) (Good)

(Participation)

(Return of Improvement)

(PDCA)

7

2.2

(2555) [1]

1.53% 0.53%

(2555) [2]

Magnetic Breaker

1.62% 0.55% 2.0%

0.89% (2555) [3]

(2555) [4]

6.17%

2.30%

3.

3.1

1)

(Genba) 2) (Genbutsu) 3) (Genjitsu)

3.2

(Check

Sheet) (Pareto principle)

3.3

(Cause and effect diagram)

3.4

(P-D-C-A) (Deming Cycle)

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4.

4.1

1

1

4.2

2

2

� � � Cap� � � � �

63.4%

4.3

3

3

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2

2

Mandrel

Cap

Cap

Extrusion

4.4

4.4.1 -

-

Cap

Mandrel Cap

Cap

Cap

One Point Cap

-

Cap

( Cap) Cap Cap

Cap Cap

Cap Cap 3

1, 2 3 1

Cap 2

Cap 3 Cap

Cap 2

One Point Cap

-

21.0 ± 0.2

17.1 ± 0.2

21.0

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17.1 ± 0.2

Cap

0.2 3

20.8, 20.6 20.4

17.1 ± 0.2

20.6 ± 0.2

4.4.2

. . 2555

1 34,750

406 1.16

3

3

( ) ( )

33,849 34,750

864 406

% 2.55 1.16

65,127.6 781,531.2

5.

Cap

2.55 1.66

65,127.6 781,531.2

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