Situation: “The Drawing” vs. “The Reality”

There was once a piece of equipment that consisted of two plates separated by several spacers. In between the plates there was a large pin and two large wheels. Due to wear in the pin and wheel bearings, this was sent to a fabrication shop to be rebuilt.

When I visited the fab shop with the drawing, we found that one plate had been welded to the spacers while the other plate was bolted into the spacers.

The drawing indicated that the plates were to be joined by bolting through the spacers to nuts on the other side.

The shop manager looks at me and wants to know how to build the new plates.

Behavior: “Stick with the Drawing!”

I thought about the problem in terms of design for operability. I could see no functional difference between bolted and welded construction.

I thought about the metallurgy of the plates. Although it was a hard steel, the shop had the pre-heating and slow-cooling capability to do the welding properly. The edge went to machining because the plates would not need an extra setup for the bolt-holes while welding would require an extra setup. Yet that wasn’t reason enough to favor machining.

I thought about maintainability and future repair complexity. If we bolted the part, it would be easier to disassemble. Aha! “Stick with the drawing” I told the shop manager, and gave him some extra instruction on how to fasten the pieces together.

Outcome: “Won’t Fit!”

When the assembly arrived back to the plant, it looked good. I was pleased… until I got a call from the mechanics who were less than enthused. Apparently, the bolt head interfered with a bracket that had been installed just behind the assembly. There was no way that assembly was going to fit as constructed, and we didn’t have the capability at the plant to do the welding properly.

The entire assembly would have to be sent back to the shop, delaying completion of the job by several days. And it was completely my fault.

Lesson: Always Ask Why

The primary lesson here was that I should have looked harder for a reason why one plate had been welded. Even under time pressure, I should have found someone who had first-hand experience with the original modification, or at least with installing this piece of equipment, to find out the reason it was different from the drawing.

Rather than expedite repair, my lack of research resulted in a delay.

However, in the spirit of taking the lesson that I had just paid for, the drawing was modified to reflect the new reality. One plate was welded to the spacers, and to facilitate disassembly the spacers were blind drilled and tapped to accept a bolt from the other side. There were several other issues that were addressed by creating drawings that had not previously existed. Future repairs will now avoid this problem without anyone having to take time to do the research, and without the shop having to try and reverse engineer worn parts.

Book Review: 5S for Operators: 5 Pillars of the Visual Workplace by Productivity Press

This is a simple book on 5-S for people who aren’t interested in a bunch of theory, but just want to get right to the two key points:

1. What’s in it for me?
2. What exactly do you want me to do?

The five pillars introduced to operators (or supervisors) are:

1. Sort: separating needed from unneeded items
2. Set in Order: making a place for everything (that is needed) and putting everything in its place
3. Shine: making sure everything stays clean (reasons for this are described in detail in TPM for Supervisors)
4. Standardize: institutionalizing the first three pillars
5. Sustain: making the first four pillars habitual

Key Points

• To Sort means more than to organize. It means to decide what is necessary for upcoming production and removing all else from the area. Items not needed are red-tagged.
• When an item is red-tagged, management can decide to choose between discarding it, selling it, returning it to the vendor, lending it, moving it, or centralizing its storage.
• To Set in Order means to decide on appropriate locations for all tools and materials that will stay in the area and improving the layout of parts and machines to reduce wasted motion.
• To Shine has several benefits and is more than janitorial work. Shine makes the workshop a more pleasant place to work.
• Cleaning equipment in the Shine phase is the same as inspecting. Cleaning for the purpose of inspecting means finding and fixing small defects that increase variability in the machine.
• To Standardize means to document and schedule tasks related to Sort, Set in Order, and Shine.
• Although we call the fifth pillar “Sustain” it is actually a form of continuous improvement. Once the first four pillars are in place, management can receive and implement improvement suggestions, post posters and newsletters, and designate focus months.

Useful Features

• Example Red Tag (page 37)
• Example Job Cycle Chart (page 85)

Table of Contents

Chapter 1: Getting Started

Chapter 2: Introduction and Overview

Chapter 3: The First Pillar: Sort

Chapter 4: The Second Pillar: Set in Order

Chapter 5: The Third Pillar: Shine

Chapter 6: The Fourth Pillar: Standardize

Chapter 7: The Fifth Pillar: Sustain

Chapter 8: Reflections and Conclusions

Further Reading About the 5S System

From TPM for Supervisors by Kunio Shirose:

OEE Improvement Process

1. Measure the extent of each of the six big losses
2. Determine how much each loss affects OEE
3. Find out what problems stand in the way of improving availability, performance rate, and quality rate
4. Determine targets and orientations needed to solve problems discovered in step 3
5. Find out how higher equipment effectiveness will affect cost-cutting and profit-boosting

The Six Big Losses

1. Breakdown losses
2. Setup and adjustment losses
3. Idling and minor stoppage losses
4. Speed losses
5. Quality defects and rework
6. Startup/yield losses

From TPM for Supervisors by Kunio Shirose:

1. It aims at getting the most efficient use of equipment (i.e. overall efficiency)
2. It establishes a total (companywide) PM system encompassing maintenance prevention, preventive maintenance, and improvement-related maintenance.
3. It requires the cooperation of equipment designers and engineers, equipment operators, and maintenance workers.
4. It involves every employee in the company.
5. It promotes and implements PM through small-group or team activities.

Book Review: Maintenance and Reliability Best Practices by Ramesh Gulati

Key Concepts

• The role of maintenance is to preserve the function of an asset, not to run the asset itself. (For an explanation, see the chapter on PM Optimization, which describes RCM.)
• Condition-Based Maintenance (CBM) has an advantage over time-based maintenance when the life of the equipment is variable or not known with much certainty.
• In maintenance Planning & Scheduling (P&S), the planner determines what and how, and the schedular determines who and when.
• TPM, 5-S, and Visual Workplace and fundamental tools in operations reliability.
• Lagging indicators show after-the-fact results. Leading indicators are process measures. Well-designed and measured leading indicators are better are identifying sustainable performance improvements.
• The generation gap plays a signficant role in workforce management. While individuals vary in their motivations, attracting talent from each of the generations requires different approaches. For example, Baby Boomers often prefer the prestige of job titles, opportunities for networking and learning, and long-term benefits. Generation Y prefers work schedule flexibility, change and challenges, and work that has a higher meaning.

Noteworthy Features

• Calculations for economic order quantity (EOQ), page 117
• Calculations for estimating reliability, page 138
• Summary of CBM/PdM technologies, p. 215
• Brief description of several maintenance & reliability analysis tools (fishbone, FMEA, standards, Pareto, RCA, Six Sigma, etc.) p. 308
• List of trends and practices that are important to understand. p. 357

Limitations

• The Basic Test on Maintenance and Reliability Knowledge (chapter 1) had some poorly-worded questions that made the intent unclear. Here are several examples with my comments.
• Question 3 . All maintenance personnel’s (craft) time is covered by work orders.  T/F? Answer: “true” in order to ensure maintenance and repair costs are accurate. [My answer: false. Breaks and lunches are not generally covered by work orders.]
• Question 7: Utilization of assets in a world-class facility should be above 98%. T/F? Answer: “true.” [Can we possibly be thinking of the same meaning of asset utilization?]
• Question 12: It is a common practice for operators to perform PMs. T/F? Answer: “true,” assuming the organization is deploying TPM. [But the question does not say anything about TPM. The question asks if it is "common" for operators to perform PMs, not whether it is a good or best practice or whether it is a component of TPM.]
• Question 13: P-F interval can be applied to visual inspections. T/F? Answer: “true.” [I still don't know what the question means by "applied." Visual inspections do not detect faults until near the end of the failure curve, so as a fault-finding task it will have to be done more frequently to ensure the fault is caught before total breakdown. Is this what the question means?]
  
• Question 16: The primary purpose of scheduling is to coordinate maintenance jobs for the greatest utilization of the maintenance resources. T/F? Answer: “true.” [My answer: false. The purpose of scheduling is to maximize return on capital investments by getting the right work done at the right time and removing efficiency roadblocks. Maximizing maintenance utilization is a purpose only insofar as it promotes ROI. Therefore, the given answer is only a partial truth.]

Table of Contents

Chapter 1: Introducing Best Practices

Chapter 2: Culture and Leadership

Chapter 3: Understanding Maintenance

Chapter 4: Work Management: Planning and Scheduling

Chapter 5: Materials, Parts, and Inventory Management

Chapter 6: Measuring and Designing for Reliability and Maintainability

Chapter 7: The Role of Operations

Chapter 8: PM Optimization

Chapter 9: Managing Performance

Chapter 10: Workforce Management

Chapter 11: M&R Analysis Tools

Chapter 12: Current Trends and Practices