Shortening of Consumables Replacement Time
Laser unit consumables need to be replaced periodically (Scheduled Online Downtime); otherwise, they can cause a laser to fail (Unscheduled Offline Downtime). Shortening of the consumables replacement time greatly contributes to shortening either of the above downtimes. It also allows the users to more easily schedule periodic replacement of laser unit consumables. Herein, we explain the plan and approach for shortening the consumables replacement time.
5. Shortening of Consumables Replacement Time
5-1. Present Status and Shortening Plan
Table 1 shows the time required for replacing each of the GT40A’s major consumables*.
| Module | Current（hours） | Target（hours） |
| AMP chamber | 7 | 4.5 |
| OSC chamber | 8 | 5.5 |
| LN module | 4.5 | 3 |
| AMP front module | 4 | 3 |
| AMP rear module | 4 | 3 |
| Monitor module | 5 | 2.5 |
*The time listed here for replacing each module may vary slightly for
laser models other than the GT40A.
Our aim is to shorten the replacement time for major consumables by approx. 30%. The approach for shortening the replacement time is explained, as follows
5-2 Approaches for Shortening Replacement Time
The replacement time can be shortened in the following three phases:
Phase 1
Replacement work items to be immediately shortened, since the know-how and proven records are already provided
Each consumable is replaced according to the replacement procedure manual. For replacement of a consumable, the same work items are basically repeated. By repeating the same work items, a skilled field service engineer can optimize them. This optimization enables shortening of the work time without affecting the quality of the replacement work. In Phase 1, the optimized work procedures are consolidated and reflected in the actual manual so as to allow all the service engineers to shorten the replacement time.
Phase 2
Replacement work items that require changing of the procedures and checking of the work quality
As described above, all the replacement work items are performed according to the replacement procedure manual. Each of replacement procedures includes a variety of measurements and checks that cause the replacement time to be increased. In Phase 2, the methods for such measurements and checks as above are reviewed to shorten the replacement time. However, this is achieved not by just reducing the number of measurements and checks to ensure the laser performance, but also by appropriately reducing their number based on the accumulated data and careful decisions made by the engineers in charge of development.
Phase 3
Replacement work items that require a drastic change, such as introduction of a new tool
In Phase 3, the replacement time is shortened by introducing a new tool, or changing or adding a hardware component. For example, replacement of a laser chamber, one of major consumables, requires passivation to optimize the chamber performance. Passivation is performed to evacuate impurities accumulated in a laser chamber while it has been stored. Currently, this passivation work needs to be performed with the laser chamber mounted in the laser unit. To shorten the replacement time, a new tool is introduced to evacuate impurities from the laser chamber before it is mounted in the laser unit. In addition, we also plan to improve the tool to achieve the target replacement time.
5-3 Shortening Replacement Time by Simultaneous Replacement of Consumable Modules
We have explained the approaches for shortening the time for replacing a single consumable in the previous section. On the other hand, there may be cases in which the replacement time can be reduced by replacing multiple modules simultaneously.
For example, replacement of the AMP and OSC chambers currently requires 7 hours and 8 hours (a total of 15 hours), respectively. The GRYCOS (Gigaphoton Recycled Chamber Operation System) now being introduced enables simultaneous replacement of these two chambers. Use of the GRYCOS allows the replacement time to be shortened to 10 hours, because the measurements and checks to be performed for each chamber need not be duplicated for simultaneous replacement; thus, the replacement time can be shortened if they are performed simultaneously.
We at Gigaphoton will continue working on reducing downtime by studying the shortening of individual replacement times as well as more efficient operations that will result in shortening of the total replacement time.
