Machine downtime monitoring, downtime tracking and reduction
Every minute of time on a machine is precious. Each minute that the machine works, it makes money for us. Each minute that it is idle, we lose money. Once we have lost a second in downtime, we can never recover it. Think of a CNC machine or a pressure die casting machine costing Rs. 1000 per hour, or Rs. 16 per minute. One minute lost is Rs. 16 lost. This is why machine downtime monitoring or downtime tracking and reduction is critical to profits.
Machine downtime monitoring is aimed at 2 types of downtime:
Downtime due to work ethics issues: These could be coming in late at the start of the shift, leaving early at the end of the shift, extended meal breaks, sleeping in the night shift, etc.
Downtime due to systems issues: Power shut downs, no raw material, machine breakdown, high setup times, accidents, etc.
The problem is that you cannot do anything about this because you do not know the durations of the downtimes, and what their causes are, without downtime tracking. A machine monitoring system tells you this, and enables you to take corrective action. It helps you completely eliminate work ethics issues, and substantially reduce systems issues. Downtime details, downtime analysis and Pareto charts in the machine downtime monitoring system enable you to identify the top causes of downtime, focus on them and reduce downtimes.
Machine downtime tracking – downtime at shift changes
A machine downtime monitoring system can detect and report downtimes at the start and end of the shift. These are caused by the operator starting production late at the at the start of the shift, or stopping production early at the end of the shift.
Here is a real example of downtime tracking at shift change. The report from LEANworx Cloud downtime tracking software shows the downtimes over a week at the start and end of the 1st and 2nd shifts. This is on a machine running 2 shifts. Shop supervisors are present only between 9 AM and 5 PM.
On Day 1, second shift, the operator left 47 minutes before 10 PM, which is the shift end. See row 2, ‘Downtime at end’ column.
On day 2 in the second shift he left 41 minutes before the shift end.
There are a number of such instances in the report.
The numbers highlighted by arrows show the bigger downtimes.
In the 1st shift, production started quite late on a couple of days, and in the 2nd shift the production stopped early almost every day.
The downtime tracking shows that late starts and early stoppage adds up to almost 5.5 hours over the week, as shown by the total at the bottom. The machine is a CNC VMC costing Rs. 900 per hour, which means the cost of this downtime was Rs. 5000 in one week. This is purely a work ethics issue, and can be easily fixed. Just print out and display this report from the machine downtime monitoring system for all machines to everbody else, on the shop notice board. There’s no need to talk to any operators, point out the issue, or do anything else.
Machine downtime monitoring at night
Here is an example of downtime tracking data for the night shift, and how it enables you fix downtimes caused by a work ethics issue – operators sleeping in the night shift.
This is a real report from an actual shop floor, showing the operator not working in the second half of the night shift. Basically sleeping between 2 AM and 6 AM. This is from a shop that runs 3 shifts, with only half the machines running in the 3rd shift, when there are no supervisors present. This screen shot from the LEANworx Cloud downtime tracking reports shows the production every hour for 3 shifts, over 5 days. Each row is a shift, and columns show the production in each hour of the 8-hour shift. The last column shows the total production in the shift.
You will notice that the production in the 1st and 2nd shifts is typically around 45, while in the 3rd shift it is less than 30 (the numbers highlighted with arrows). The 3rd shift production is almost half that in the other shifts. Notice the numbers in the red ovals ? These are the hourly production in the second half of the 3rd shift, between 2 AM and 6 AM. The production is almost zero in this period, every day. This can mean only one thing. The operator is sleeping for half the night shift ! The machine in this report costs Rs. 900 per day, meaning this downtime is costing Rs. 20,000 every week.
You can easily fix this through downtime tracking with a machine monitoring system.
Machine downtime monitoring – strategy to get RAPID benefits from downtime tracking
Divide the implementation into 2 phases:
Phase 1: Tackle the LOW HANGING FRUIT – downtime tracking for work ethics issues.
Phase 2: Tackle the HIGH HANGING FRUIT – downtime tracking for other issues.
The low hanging fruit require very little time (typically 2 weeks) and no investment in equipment or people for machine downtime monitoring.
The high hanging fruit may require investment in equipment or people. E.g., Reducing setup times may require investment in improved fixturing, modular or quick change tooling, etc. Reducing machine breakdowns may require more people, replacing some machine parts or machines, etc.
Reduce losses due to work ethics issues
This gets you:
Rapid downtime reduction, in just 2 weeks.
Rapid culture change in the shop floor personnel.
The low hanging fruit from downtime tracking accounts for 5-15% of the total available time. Eliminating this is equivalent to getting 5%-15% more production capacity immediately.
To do this, all you have to do is print each day’s ‘Downtime shift start-end’ report from the machine downtime monitoring system, and put it up on a notice board, for all machines.
All personnel on the shop floor know every else’s starting and stopping times, and there is no need to talk to anyone or take disciplinary action.
This also starts a culture change among personnel, getting them to understand the importance of downtime.
Reduce losses due to system downtimes caused by setup time, machine breakdowns, no raw material, inspection, etc.
You can do this in 3 steps.
|Step||Task||Extent of benefits||Time to do|
|1||Reduce downtime at shift change||10-15 % of total available time*||2 weeks|
|2||Reduce process downtimes||10-15% of total available time,|
assuming a 50% reduction in this.**
|3||Reduce Machine breakdowns||10-15% of total available time,|
assuming a 90% reduction in this.***
* Most shop floors lose 1 to 3 hours in a day due to late starting and early stoppage in shifts. At 22 hours per day working, this is 5-15% of the scheduled time.
** System downtimes account for 20-30% of the total time. You can typically reduce these by 50%.
***Breakdowns account for 20-30% of the total time. You can typically reduce these by 90% over time, through preventive maintenance and autonomous maintenance.
Steps 2 and 3 can also be done in parallel.
These numbers come from our own experience of downtime tracking with various customers of LEANworx machine downtime monitoring system.