Part II: How OCE Impacts Your Bottom Line
Ralph W. “Pete” Peters, President
Craft Labor-A Terrible Thing to Waste: Improving Overall Craft Effectiveness is very key question we need to answer. Getting maximum value from craft labor resources and higher craft productivity requires measurement and knowing where you are now.
Maintenanceoperations that continue to operate in a reactive, run-to-failure, fire fighting mode and disregard implementation of today’s best practices will continue to waste their most valuable asset and very costly resource - craft time. Typically, due to no fault of the craft work force, surveys and baseline measurements consistently show that only about 30 to 40 percent of an eight-hour day is devoted to actual,hands-on wrench time.
It is very important to understand; “How your valuable craft time can slip away” as illustrated in Figure 2. Best practices such as effective maintenance planning/scheduling, preventive/predictive maintenance, more effective storerooms and parts support all contribute to proactive, planned maintenance and more productive hands on, “wrench time”.
Measuring and improvingoverall craft effectiveness (OCE) must be one of many components to continuous reliability improvement process and total asset management. As we discussed in Part I, OCE includes three key elements very closely related to the three elements of the OEE Factor.
Overall Craft Effectiveness(OCE) | Overall Equipment Effectiveness(OEE) | Elements of OEE and OCE |
1. Craft Utilization or Pure WrenchTime (CU) |
Asset Availability/Utilization (A) | Effectiveness |
2. Craft Performance (CP) | Asset Performance (P) | Efficiency |
3. Craft Service Quality (CSQ) | Quality of Asset’s Output (Q) | Quality |
Craft Utilization (CU): The first element of the OCE Factor is Craft Utilization or pure wrench time. This element of OCE relates to measuring how effective we are inplanning and scheduling craft resources so that these assets are doing value-added, productive work (wrench time). Effective planning/scheduling within a proactive maintenance process is key to increased wrench time and craft utilization. It’s having an effective storeroom with the right part, at the right place in time to do scheduled work with minimal non-productive time on the part of the craftsperson or crew assigned to the job.
Pure wrench time is just that and does not include time caused by the following:
1. Running/traveling from emergency to emergency in a reactive, fire fighting mode
2. Waiting on parts and finding parts or part information
3. Waiting on other asset info, drawings, repair instructions, documentation etc.
4. Waiting for the equipment to be shut down5. Waiting on rental equipment or contractor support to arrive at job site
6. Waiting on other crafts to finish their part of the job
7. Traveling to/from job site
8. Make-ready, put away or shop clean up time
9. Meetings, normal breaks, training time and excessive troubleshooting due to lack of technical skills
10. Lack of effective planning and scheduling
CraftUtilization (or wrench time) can be measured and expressed simply as the ratio of:
Total Productive (Wrench Time)
CU% = Total Craft Hours Available & Paid x 100
Improve Wrench Time First: Go on the attack to increase wrench time in your operation even if you do nothing to improve the other two OCE Factors; Craft Performance and the Craft Methods and Quality level. As we will see in the followingexamples, very dramatic and significant tangible benefits can be realized with just focusing on increasing wrench time. Improvement of from 20 to 30 percentage points can typically be expected just from more effective maintenance planning and scheduling. Let’s now look at several examples showing the value of craft utilization improvement within a 20-person work force with an average hourly rate...