米其林工厂标准工时、周期时间分析(cycle time)

TBM Second Stage Beijing Machine C.O. Report 1. C.O. Basic Information

Reference: TBM second stage operator Date: 08/14/2003

Shift: middle shift (1B) Site: B-02

Operator: 2954 Analyst: Zhang Li

Start time: 14:48End time: 22:55

Product: 032.011 (175/65R14 82T R23 )

2. C.O. Result

Production: 170

3. Cycle Time Analysis

Time for building one bandage (not including weighing & VCVB)

Total Average: 1.54 min

Total Median: 1.45min

From the Cycle Time Trend Chart, the real cycle time(not including weighing & VCVB) can be 1.35 min.

Time of Weighing & VCVB

2 actions, weighing and VCVB, are required now to get the quality of bandages

controlled. After time study in this continuous observation, the normal contribution to the cycle time of these 2 actions is defined as 0.15 min.

Cycle Time

Through time study, the target cycle time is figured out as 1.50 min/unit.

4.Improvement

1) Material Change

Constraints:

The constraint in changing material is NST. Operators must unload the NST cart from the machine and transport it to the changing area. Also they should transport the NST bobbin from storage to changing area to get them changed. After changing, they would push the cart to the machine. Fairly long time is wasted in transporting.

Suggestions:

If we add cranes besides the machine like Krupp building machine on which operators can easily change the NST bobbin, at least half of the NST changing time will be saved.

We’ll get higher efficiency.

Target: Total Time for Changing 25 mins

2)Back Roller Improvement

Constraints:

Not all the back rollers work well now. Many operators have to brush cement to every carcasse to ensure the press quality. This action adds extra cycle time and causes the potential defect of the bandages.

Suggestions:

Refer to Mr. Zhou Xiaomin’s recommendation, we find the back roller of machine No. B-01~B-04 working well. If the semi-produced goods are good, operators can scarcely brush the cement to the carcasse. We will discuss with BE about the

modification issue.

3)Quality Level

Through above table and pie chart, we can easily find that in this shift, brushing cement causes the main quality time loss. If we get stable semi-produced material quality and get the back roller modified, we can cancel the action of brushing. In addition, as soon as we solve the NST/NSF

joints problem and standardize the use of NST underlayer, our quality time can be controlled into 5mins.

Target: Total Quality Time 5mins

4)

Constraints:

Time loss caused by machine in this shift arrived at 69.19 min. It shows that there are problems in our maintenance.

Suggestions:

We should carry on an investigation of the machine and set up the machine dossier to clarify our machines status and improve the machine status. And this

should be extend to all the machines in TBM.

Target machine time is within 10mins.

THE LESS, THE BETTER

5)Additional Time